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Astron Power Supplies Questions
Hi guys
I'm looking to pick up one of these for a couple receivers. Now I seem to have run into a concern. I did some research and found several models that don't offer crowbar overvolt protection. The RS-3a, RS-4a, 5a, and 4L and 5L. But, I see they have a primary fuse on back. Now take the RS-10a. It has crowbar protection, but no fuse for a primary overvolt. So I figured if they have crowbar, they don't need a fuse. But now I have found Astron models with crowbar but some use a fuse while others don't. So what's the story here? Which one is best? One that uses both a fuse and has built in crowbar protection or it doesn't matter as long as they have crowbar? Why do some use both then? Why do some not use a fuse at all? That doesn't seem to make sense. Thanks for replies Lucky |
You want a crowbar and a fuse.
Avoid switchmode supplies like the plague. This is a link to one review of the RS-10a: http://www.eham.net/reviews/detail/3726 This link to a dagram shows a fuse: http://www.repeater-builder.com/astr...ron-rs-10a.jpg A long time ago in a different life (20+ years ago) I was responsable for the operation of a 2 mtr repeater and I picked a Atron supply that is still chugging along with no trouble. I don't remember which Astron but at least back then, they made great supplies. I added a surplus magnetic circuit breaker between the output of my Lambda ~15A 12V supply and my equipment, followed by a seperate fast acting, no falses ?(so far) crowbar. This is the BEST OVP (Over Voltage Protector) I have seen in 30+ years of working in electronics. Added a heavy si diode wired to shunt reverse voltage to ground. This is located in the power distribution section of my system. With this I can directly power my radio room from my car, for emergencies, and won't have to worry abvout areverse connection,or nasty spikes damaging my equipment. Power supply on floor feeds voltage/current monitoring with R&OVP and breakers to protect and alllow me to power down sections to reduce power load. Sounds complex and expensive, but it wasn't and I bought everything surplus. The distirbution sections has stayed "the same" for the last 20 years, I have gone through several power supplies. I have connections for 2 lead acid gell cells, and an outside connection to allow an external +12V power source. Think modular. Build it in sections as needed. Terry Terry |
wrote in message ups.com... You want a crowbar and a fuse. Avoid switchmode supplies like the plague. This is a link to one review of the RS-10a: http://www.eham.net/reviews/detail/3726 This link to a dagram shows a fuse: http://www.repeater-builder.com/astr...ron-rs-10a.jpg A long time ago in a different life (20+ years ago) I was responsable for the operation of a 2 mtr repeater and I picked a Atron supply that is still chugging along with no trouble. I don't remember which Astron but at least back then, they made great supplies. I added a surplus magnetic circuit breaker between the output of my Lambda ~15A 12V supply and my equipment, followed by a seperate fast acting, no falses ?(so far) crowbar. This is the BEST OVP (Over Voltage Protector) I have seen in 30+ years of working in electronics. Added a heavy si diode wired to shunt reverse voltage to ground. This is located in the power distribution section of my system. With this I can directly power my radio room from my car, for emergencies, and won't have to worry abvout areverse connection,or nasty spikes damaging my equipment. Power supply on floor feeds voltage/current monitoring with R&OVP and breakers to protect and alllow me to power down sections to reduce power load. Sounds complex and expensive, but it wasn't and I bought everything surplus. The distirbution sections has stayed "the same" for the last 20 years, I have gone through several power supplies. I have connections for 2 lead acid gell cells, and an outside connection to allow an external +12V power source. Think modular. Build it in sections as needed. Terry Terry There is a 10a on Ebay for $10 but it's missing the front print and don't know if it's missing the fuse too. I think the best way to go is buy one new. You just don't know the real condition of it and how long it was used. The best one I could find new for the price is the Astron RS-7a. $55. So it's either spend like $65 on a brand new one or buy one off Ebay. What do you think? $10 for a 10A might not be too bad though if I use a surge protector with it. Thanks Lucky |
I wouldn't hesitate to buytheon you mention. But I don'tknow what
your electronic skills are. It could be a very good deal, or a boat anchor. Take a look at the diagram in the 2nd link and decide if you could rebuild one. The transformer, caps, and heatsink are the expensive parts. If you have those repair is easy and fairly inexpensive. But there is something to be said for a brand new, and under warrenty item. Terry |
wrote in message ups.com... You want a crowbar and a fuse. Avoid switchmode supplies like the plague. This is a link to one review of the RS-10a: http://www.eham.net/reviews/detail/3726 This link to a dagram shows a fuse: http://www.repeater-builder.com/astr...ron-rs-10a.jpg A long time ago in a different life (20+ years ago) I was responsable for the operation of a 2 mtr repeater and I picked a Atron supply that is still chugging along with no trouble. I don't remember which Astron but at least back then, they made great supplies. I added a surplus magnetic circuit breaker between the output of my Lambda ~15A 12V supply and my equipment, followed by a seperate fast acting, no falses ?(so far) crowbar. This is the BEST OVP (Over Voltage Protector) I have seen in 30+ years of working in electronics. Added a heavy si diode wired to shunt reverse voltage to ground. This is located in the power distribution section of my system. With this I can directly power my radio room from my car, for emergencies, and won't have to worry abvout areverse connection,or nasty spikes damaging my equipment. Power supply on floor feeds voltage/current monitoring with R&OVP and breakers to protect and alllow me to power down sections to reduce power load. Sounds complex and expensive, but it wasn't and I bought everything surplus. The distirbution sections has stayed "the same" for the last 20 years, I have gone through several power supplies. I have connections for 2 lead acid gell cells, and an outside connection to allow an external +12V power source. Think modular. Build it in sections as needed. Terry Terry You know what, screw Ebay. My R75 is almost brand new and I love my Lowe HF-150 so why not "splurge a little" :) and buy a new one? I just bought a brand new Astron RS-7a. $45.80 was the cheapest I could find it plus $12 shipping. It weighs 10lbs. I think I did the right thing buying a new one. Lucky |
"Lucky" wrote in message ... wrote in message ups.com... You want a crowbar and a fuse. Avoid switchmode supplies like the plague. This is a link to one review of the RS-10a: http://www.eham.net/reviews/detail/3726 This link to a dagram shows a fuse: http://www.repeater-builder.com/astr...ron-rs-10a.jpg A long time ago in a different life (20+ years ago) I was responsable for the operation of a 2 mtr repeater and I picked a Atron supply that is still chugging along with no trouble. I don't remember which Astron but at least back then, they made great supplies. I added a surplus magnetic circuit breaker between the output of my Lambda ~15A 12V supply and my equipment, followed by a seperate fast acting, no falses ?(so far) crowbar. This is the BEST OVP (Over Voltage Protector) I have seen in 30+ years of working in electronics. Added a heavy si diode wired to shunt reverse voltage to ground. This is located in the power distribution section of my system. With this I can directly power my radio room from my car, for emergencies, and won't have to worry abvout areverse connection,or nasty spikes damaging my equipment. Power supply on floor feeds voltage/current monitoring with R&OVP and breakers to protect and alllow me to power down sections to reduce power load. Sounds complex and expensive, but it wasn't and I bought everything surplus. The distirbution sections has stayed "the same" for the last 20 years, I have gone through several power supplies. I have connections for 2 lead acid gell cells, and an outside connection to allow an external +12V power source. Think modular. Build it in sections as needed. Terry Terry You know what, screw Ebay. My R75 is almost brand new and I love my Lowe HF-150 so why not "splurge a little" :) and buy a new one? I just bought a brand new Astron RS-7a. $45.80 was the cheapest I could find it plus $12 shipping. It weighs 10lbs. I think I did the right thing buying a new one. Lucky Guess what? I cancelled the damn order. After looking carefully thru the finer print, it seems they are in "perfect condition returns" That why $45.80 Hate that crap. You see these deals on radios till you call and finally found out "our loss is your gain" is that are "open box" items or "factory refurbished" Lucky |
beerbarrel wrote: On Mon, 23 May 2005 15:13:01 -0400, "Lucky" wrote: wrote in message oups.com... You want a crowbar and a fuse. Avoid switchmode supplies like the plague. This is a link to one review of the RS-10a: http://www.eham.net/reviews/detail/3726 This link to a dagram shows a fuse: http://www.repeater-builder.com/astr...ron-rs-10a.jpg A long time ago in a different life (20+ years ago) I was responsable for the operation of a 2 mtr repeater and I picked a Atron supply that is still chugging along with no trouble. I don't remember which Astron but at least back then, they made great supplies. I added a surplus magnetic circuit breaker between the output of my Lambda ~15A 12V supply and my equipment, followed by a seperate fast acting, no falses ?(so far) crowbar. This is the BEST OVP (Over Voltage Protector) I have seen in 30+ years of working in electronics. Added a heavy si diode wired to shunt reverse voltage to ground. This is located in the power distribution section of my system. With this I can directly power my radio room from my car, for emergencies, and won't have to worry abvout areverse connection,or nasty spikes damaging my equipment. Power supply on floor feeds voltage/current monitoring with R&OVP and breakers to protect and alllow me to power down sections to reduce power load. Sounds complex and expensive, but it wasn't and I bought everything surplus. The distirbution sections has stayed "the same" for the last 20 years, I have gone through several power supplies. I have connections for 2 lead acid gell cells, and an outside connection to allow an external +12V power source. Think modular. Build it in sections as needed. Terry Terry You know what, screw Ebay. My R75 is almost brand new and I love my Lowe HF-150 so why not "splurge a little" :) and buy a new one? I just bought a brand new Astron RS-7a. $45.80 was the cheapest I could find it plus $12 shipping. It weighs 10lbs. I think I did the right thing buying a new one. Lucky You think someone on ebay would sell you one? Good question. dxAce Michigan USA |
wrote in message oups.com... I wouldn't hesitate to buytheon you mention. But I don'tknow what your electronic skills are. It could be a very good deal, or a boat anchor. Take a look at the diagram in the 2nd link and decide if you could rebuild one. The transformer, caps, and heatsink are the expensive parts. If you have those repair is easy and fairly inexpensive. But there is something to be said for a brand new, and under warrenty item. Terry How good are the Pyramid PSU's?? Lucky |
I have seen people use them but an Astron is much better. Also,
If you look around on ebay and QTH.com and QRZ.com you can usually find a 20 amp for around $40 - $80 , with or without meters, in good working order. 20 amp might be over kill for you now but it will last forever! Even an Astron 12 amp would be OK for receivers. These supplies will run forever without a light receiver load. I have an astron 50 amp supply that has been on since 1985!!!!! Remember, you only want to buy a supply one time. If the one you get is just enough for your needs today, what happens when you get a few more pieces next year and now your supply is too small? Have fun!!! ================================================== ===== Lucky wrote: How good are the Pyramid PSU's?? wrote in message roups.com... I wouldn't hesitate to buytheon you mention. But I don'tknow what your electronic skills are. It could be a very good deal, or a boat anchor. Take a look at the diagram in the 2nd link and decide if you could rebuild one. The transformer, caps, and heatsink are the expensive parts. If you have those repair is easy and fairly inexpensive. But there is something to be said for a brand new, and under warrenty item. Terry How good are the Pyramid PSU's?? Lucky |
POS
I have seen several and even the linear ones are way too noisy. Go with an aston. Even a returned unit could ber a very good deal. Lot's of items are returned that have no problem I wouldn't hesitate to go for a factory refurbished supply. If you can afford it, spring for meters. It is nice to be able to look at the voltage adn currentmeters every now and then just to check that things are normal. I had an old Clegg rock bound 2 mtr rig that started drawing about 2 amps on squelched receive. The amp meter showed me an unexpected load, so I was able to catch a minor problem before it became a big one. Terry |
wrote in message oups.com... POS I have seen several and even the linear ones are way too noisy. Go with an aston. Even a returned unit could ber a very good deal. Lot's of items are returned that have no problem I wouldn't hesitate to go for a factory refurbished supply. If you can afford it, spring for meters. It is nice to be able to look at the voltage adn currentmeters every now and then just to check that things are normal. I had an old Clegg rock bound 2 mtr rig that started drawing about 2 amps on squelched receive. The amp meter showed me an unexpected load, so I was able to catch a minor problem before it became a big one. Terry OK thanks for the heads up. Some reviews were good but they are too cheap and I never heard of them either. Well I cancelled the refurbished one. I'm not paying $58 {shipping and taxes} included for a fixed one. In that case I take a chance on Ebay for much less. Heck an Astron RS-10A went for $22 yesterday. OK this is the story I hear on looking for newer Astrons. It seems if the power cord is able to be disconnected from the PSU, it is a newer one. They went in this order from older to newer. 1] oldest is the PSU's with undetachable power cords with the fuse built into the radios circuitry. You can't see the fuse or access it unless you open up the radio. 2] PSU's with undetachable power cords with a screw in type fuse seen on back of unit. 3] The newest is the power cord is detachable and the small glass fuse is in back of the radio but it's in the radios powercords receptacle. If you can get a closeup of the powercords jack, you will see a tiny picture of a fuse right above the jack. It can be changed from the outside. One with meters is not a bad idea. I'm still looking. I see an Astron with no crowbar protection but it has a screw in type fuse and I woud be using a surge protector anyhow. I read the worst that can happen with no crowbar OVP, is that the full output voltage can occur during a short. So it doesn't seem too bad if you have a a PSU that's maximum output is 15v and you don't have crowbar OVP. The most your receiver can get hit with is 15v if I am right in my interpretation of the crowbar protection failing. It does have a fuse that will blow from any heavy surges. What do you think? Crowbar that important if you have a fuse?? Lucky |
"Gen. Geroge Hammond" wrote in message ... I have seen people use them but an Astron is much better. Also, If you look around on ebay and QTH.com and QRZ.com you can usually find a 20 amp for around $40 - $80 , with or without meters, in good working order. 20 amp might be over kill for you now but it will last forever! Even an Astron 12 amp would be OK for receivers. These supplies will run forever without a light receiver load. I have an astron 50 amp supply that has been on since 1985!!!!! Remember, you only want to buy a supply one time. If the one you get is just enough for your needs today, what happens when you get a few more pieces next year and now your supply is too small? Have fun!!! ================================================== ===== Lucky wrote: How good are the Pyramid PSU's?? wrote in message oups.com... I wouldn't hesitate to buytheon you mention. But I don'tknow what your electronic skills are. It could be a very good deal, or a boat anchor. Take a look at the diagram in the 2nd link and decide if you could rebuild one. The transformer, caps, and heatsink are the expensive parts. If you have those repair is easy and fairly inexpensive. But there is something to be said for a brand new, and under warrenty item. Terry How good are the Pyramid PSU's?? Lucky So I'm to assume the more amps you have, the longer the PSU will last??ThanksLucky |
Most linear supplis have about +20V before the "pass element",
transistors. And if a transistor shorts C to E, then ~+20V will appear at the +12V output. A good OVP/crowbar is a must have! But if an otherwise good supply lacks an OVP I would add my own. The first link I gave has a diagram for a very good, in fact better then any I have ever seen built iinto any PS. The Areotech diagram specs 1% resisitors. I used 5% with no decrease in functionality. Given the orignal use was to be in aircraft, the slight performance edge offered by 1% ressitors was well worth it, that is a "life critical" mission. While I value my radios, I am more then willking to settle for a little less absolute performance. I built the first one with teh specified 1% resisitors, I built another unit with 5% resisitors, and as far as I can measure, they both trip in about ~50mS. That is 0.05S. Thats for a jump of 13.69V to +20V. I use 13.69V because that is the most commonly suggested voltage to keep lead acid gell cells "float charged". I added a 120V AC relay to lift, open, the + output from the PS so during power failures, my radios keep running. And as a rule, the larger a supply, the cooler it runs, and cool equates to LONG life. Terry |
wrote in message ups.com... Most linear supplis have about +20V before the "pass element", transistors. And if a transistor shorts C to E, then ~+20V will appear at the +12V output. A good OVP/crowbar is a must have! But if an otherwise good supply lacks an OVP I would add my own. The first link I gave has a diagram for a very good, in fact better then any I have ever seen built iinto any PS. The Areotech diagram specs 1% resisitors. I used 5% with no decrease in functionality. Given the orignal use was to be in aircraft, the slight performance edge offered by 1% ressitors was well worth it, that is a "life critical" mission. While I value my radios, I am more then willking to settle for a little less absolute performance. I built the first one with teh specified 1% resisitors, I built another unit with 5% resisitors, and as far as I can measure, they both trip in about ~50mS. That is 0.05S. Thats for a jump of 13.69V to +20V. I use 13.69V because that is the most commonly suggested voltage to keep lead acid gell cells "float charged". I added a 120V AC relay to lift, open, the + output from the PS so during power failures, my radios keep running. And as a rule, the larger a supply, the cooler it runs, and cool equates to LONG life. Terry Ok I see. I'm good with my hands, can build a computer with ease, have done lots of soldering, but when it comes to mission critical items like a PSU that could end the life of one of my radios or cause a fire, I don't trust in myself enough to do it. But, I learn very quickly. If I were to be there with you, and watch you do it once, I could repeat it. Funny how all these wall worts we use for our radios have none of these features or protection. Or even are regulated. But, it's very important to know. Using a simple Radio Shack regulated PSU got rid of the hum that was driving me batty on my HF-150. BTW, linear = regulated correct? Lucky |
Wall warts can only deliver so many ma, or for big ones an amp or 2.
A real power supply can deliver well over it's rated current for a few seconds. Long enough to turn most radios into slag. Go with one with a built in OVP/crowbar and try building an out board one later. In a extened power outage you might find it usefull to be able to draw power from you car or truck. At that time you really want to have a OVP/crowbar between your radios and vehical's electrical system. Flexiblility is important. You might want to contact the alarm companies in your area as many of the better ones retire perfectly good gell cells from alarm systems for insurance reasons. Having a burgler alarm fall during a powqer outage because a 3 year old gell cell died is real bad for business. I have several gell cells that are 10 years old and going strong. After overcharging them, heat is the biggest killer, keep them cool, under ~90F, and they will last for years. Here in central Kentucky we often have nasty T-storms that knock the power out for several hours. It is very nice to be able to listen to my radios after the storm moves out. It is true that I mainly listen to my scanners, but having a SW is very nice also. One winter's night 2 years ago the lights went out and stayed out for about 5 hours. Perfect listening conditions. No nearby TV,s PCs etc. Very RF quite. Made the extra effort for the gell cells worth while. Terry |
I run everything off a SS-18 (R8B and 30 ANC4's DA100E's and DSP's). I tried
a RS-7A but didn't like the heat it throws off. The switching supply avoids that. I fuse the output at the supply with an inline fuse (reflecting the wire gauge), and fuse each device separately with like 1/4 or 1/2 or 1-2 amp fuses where I distribute 12v to them all. A properly working power supply can easily burn up the light wires running to these things if you don't fuse it, where the internal resistance of wall warts had prevented it before you went to a central power supply. There's some birdies from the SS-18 but they're not bad; and I put the thing in the basement and run the 12v to the first floor, so there's some distance intervening as well. It does run enormously cooler. I was motivated to get the central 12v by the heat the R8B's supply throws off, that is now eliminated, as well as the growing number of wall warts I was accumulating as I added to my phased array. -- Ron Hardin On the internet, nobody knows you're a jerk. |
"Ron Hardin" wrote in message ... I run everything off a SS-18 (R8B and 30 ANC4's DA100E's and DSP's). I tried a RS-7A but didn't like the heat it throws off. The switching supply avoids that. I fuse the output at the supply with an inline fuse (reflecting the wire gauge), and fuse each device separately with like 1/4 or 1/2 or 1-2 amp fuses where I distribute 12v to them all. A properly working power supply can easily burn up the light wires running to these things if you don't fuse it, where the internal resistance of wall warts had prevented it before you went to a central power supply. There's some birdies from the SS-18 but they're not bad; and I put the thing in the basement and run the 12v to the first floor, so there's some distance intervening as well. It does run enormously cooler. I was motivated to get the central 12v by the heat the R8B's supply throws off, that is now eliminated, as well as the growing number of wall warts I was accumulating as I added to my phased array. -- Ron Hardin On the internet, nobody knows you're a jerk. Hi Ron I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? Lucky |
wrote in message oups.com... Wall warts can only deliver so many ma, or for big ones an amp or 2. A real power supply can deliver well over it's rated current for a few seconds. Long enough to turn most radios into slag. Go with one with a built in OVP/crowbar and try building an out board one later. In a extened power outage you might find it usefull to be able to draw power from you car or truck. At that time you really want to have a OVP/crowbar between your radios and vehical's electrical system. Flexiblility is important. You might want to contact the alarm companies in your area as many of the better ones retire perfectly good gell cells from alarm systems for insurance reasons. Having a burgler alarm fall during a powqer outage because a 3 year old gell cell died is real bad for business. I have several gell cells that are 10 years old and going strong. After overcharging them, heat is the biggest killer, keep them cool, under ~90F, and they will last for years. Here in central Kentucky we often have nasty T-storms that knock the power out for several hours. It is very nice to be able to listen to my radios after the storm moves out. It is true that I mainly listen to my scanners, but having a SW is very nice also. One winter's night 2 years ago the lights went out and stayed out for about 5 hours. Perfect listening conditions. No nearby TV,s PCs etc. Very RF quite. Made the extra effort for the gell cells worth while. Terry Wouldn't the gel cell need to be 12 to 13.8v though? I've heard you guys talk about gel cells for outdoor radio use. They sound interesting. So you just add the correct sized plug to the gel cell for your radios power input jack and you're good to go? Lucky |
To charge a lead acid battery regardless if
if it is liquid, like your car battery, or has a gelled electrolyt, requires a higher voltage then the nominal rated voltage be applied. Broadly speaking there afre three classes of lead acid service. Starting, cycle, and flaot. The first is your typical engine atarting service. Requires gobs of vurrent for short periods and loafs after that. Cycle is like for golf carts, fork lifts, VHS camcorders, and in truth the way I used to use a gell cell to power my SW for weekend radio picnics. Standby is for "emergency" loss of power applicaitns like emergency lightst in public areas, PC UPS and the like. And each service has different suggested charging voltages. See: http://www.osibatteries.com/pdf/Gel%...ies%202004.pdf for one take on the correct charging voltages. Cars charge batteries at up to 15V. A gell cell wll get hot and fail very rapidly at that voltage. I have found 13.69V to be good voltage. Some go as low as 13.5 or so. Much below that 13.5 and the battery will not charge. Half these for 6 volt batteries. I have a couple of 6V gell cells designed to power camcorders that I use with our DX398 for week end radio picnics. One DX398 will operate for over a day on a single battery. To get slighlty longer run time I could charge them at ~7V, but I prfer for my batteries to live longer then run longer. Everything is a trade off. Longer run time for fewer charge/discharge cycles. At home I would just operate everything from my 12 gell cells, I have linear step down regulators to reduce the 12V to 9V and 6V as needed. With each devcie protected by a OVP after the reduction regulator. If I knew a power outage was going to last a "long time", I would power our DX398s from the 6V gell cells. I scalvaged 4 PV (solar cells) from some dead lawn night lights that produce ~150mA at 4V in bright sunlight, by making 2 parallel sets of 2 in series I get 8V at ~300mA. With a simple shunt regulator I get 6.845V,more then enough to keep the gell cell topped off and operate 2 DX398s at the same time. I have a couple of older Arco ~12V PV arrays that produce 18V @.75A in bright sunshine, so I could recharge my 12V gell cells and or operate some equipment during daylight hours. Remnants from the cold war when the great nuke out seamed likely. Terry |
wrote in message ups.com... To charge a lead acid battery regardless if if it is liquid, like your car battery, or has a gelled electrolyt, requires a higher voltage then the nominal rated voltage be applied. Broadly speaking there afre three classes of lead acid service. Starting, cycle, and flaot. The first is your typical engine atarting service. Requires gobs of vurrent for short periods and loafs after that. Cycle is like for golf carts, fork lifts, VHS camcorders, and in truth the way I used to use a gell cell to power my SW for weekend radio picnics. Standby is for "emergency" loss of power applicaitns like emergency lightst in public areas, PC UPS and the like. And each service has different suggested charging voltages. See: http://www.osibatteries.com/pdf/Gel%...ies%202004.pdf for one take on the correct charging voltages. Cars charge batteries at up to 15V. A gell cell wll get hot and fail very rapidly at that voltage. I have found 13.69V to be good voltage. Some go as low as 13.5 or so. Much below that 13.5 and the battery will not charge. Half these for 6 volt batteries. I have a couple of 6V gell cells designed to power camcorders that I use with our DX398 for week end radio picnics. One DX398 will operate for over a day on a single battery. To get slighlty longer run time I could charge them at ~7V, but I prfer for my batteries to live longer then run longer. Everything is a trade off. Longer run time for fewer charge/discharge cycles. At home I would just operate everything from my 12 gell cells, I have linear step down regulators to reduce the 12V to 9V and 6V as needed. With each devcie protected by a OVP after the reduction regulator. If I knew a power outage was going to last a "long time", I would power our DX398s from the 6V gell cells. I scalvaged 4 PV (solar cells) from some dead lawn night lights that produce ~150mA at 4V in bright sunlight, by making 2 parallel sets of 2 in series I get 8V at ~300mA. With a simple shunt regulator I get 6.845V,more then enough to keep the gell cell topped off and operate 2 DX398s at the same time. I have a couple of older Arco ~12V PV arrays that produce 18V @.75A in bright sunshine, so I could recharge my 12V gell cells and or operate some equipment during daylight hours. Remnants from the cold war when the great nuke out seamed likely. Terry Thanks for the explanations Terry. I'm going to try one instead of taking 16 battries with me and HF-150. I charge up 16 2100 mAh in my "8 ata time" charger. Does 8 in 8 hours so it's not that bad. The first charger I had took like 14-15 hours! I refuse to charge the batteries in the Lowe itself. I wil not take the chance of accidents and I don't believe in the radio being in use all the time for such a simple process. I know I'm being overprotective of the radio but I think it's worth it. Lucky |
Lucky wrote:
I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? I put a fuse on the hot wire, with amps based on the carrying capacity of the wire (not the capacity of the power supply!). The wire goes upstairs from the basement, and at the upstairs end I run it into many fuse blocks, each with tiny fuses (1/4 to 2a) for each of the devices I power with it, depending on its needs. The wires that typically run into coaxial power plugs have very little capacity before overheating, and you want its fuse to blow before it (the particular wire) heats up. So no short anywhere heats up any wire. A normally functioning power supply is quite capable of burning down the house if run into typical hookup wire without some fusing. It's unintuitive because the same wire works fine at 120v, but it's amps that causes heating, not power, and there's ten times more amps (=100 times more heating) at 12v than 120v. -- Ron Hardin On the internet, nobody knows you're a jerk. |
Lucky wrote:
I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. They're usually not much good right next to the antenna (or the radio, if the antenna is on the radio), but vary in how bad the birdies they generate are. My MFJ puts out enormous birdies so I'd avoid their switching supplies. My Astron SS-18 is tolerably low. The payoff is that the switching supplies generate much, much less heat, and thus use less power if left on all the time, in particular. -- Ron Hardin On the internet, nobody knows you're a jerk. |
Ron, What gauge wire do you use to run the DC upstairs?
I have some heavy silicon jacketed welding cable that I have considered using if I ever get around to building a real exteranal battery "bank". The main killer with normal wire is the heavy IR losses. 0.5 V at 12V is a killer. I occasionaly, at rare moments mainly during T-storms, actually use my ham gear to talk. 8A max for 2mtr, about 10A on voice peaks for SSB. The rest of the time I draw less then 5 amp with every +12V device in the shack on. Which isn't all that often. I have an 15A magnetic breaker on each gell cell. And individual breakers sized to meet the normal current demands per device. I have a 6A meter, that only monitors the non ham gear. For most of my devices I use 2A mag breakers. This allows me to rapidly power down entire sections. The R2000s draw about 150mA each even when off for the clock, by switching off the +12V I avoid sneak devices that might use juice even when off. My 12Amp supply is slighlty overloaded on voice peaks, but Lambda underates their supplies. It will deliver 16 Amps for 20 minutes before it goes into thermal fold over. I have 2 clocks, on a 24Hr clock I built based on an early LSI (5314) chip with a built in backup/keep alive 9V nicad. My other clock is from my 1981 Subrau that we drove to death. The frame rusted through. Both clocks dfrasw abut 50mA with the display on, and less then 1mA displays blanked. A much better power load then the R2000s. I have based my design on what I saw in a military comm center. I have a 12A and a spare ready to turn on 12A, and my older 8A supply in the bottom of the closet. I bought all the parts surplus for less then pennies on the dollar. All told I have no more then $100 in my entire power system. And that inlcudes the PV arrays, gell cells, everything. As I mentioned before I have found the canon/amphenol 4 pin XLR connectors to be great, safe for 12V DC. The broadcast industry ony uses pins 1 and 4, I added 2 and 3 (1&2 and 3&4) this halves the IR losses, doubles the current from ~10 to 20. Each of the power loads, IC28A, HTX100 gettheir own XLR, the receive section has it's own 4 pin XLR that feeds a set of individually protected 5.5/2.1 coaxial power connectors. Presently I have 5 more scokets then devices. I mounted them on a piece of angle alumium and run male to male coaxial power cords. Makes changing things pretty simple. Each breaker is labeled to help avoid confussion. Sounds a lot more complex then it realy is. I try to only get gear that will work directly on +12V. But sometimes a good deal on "odd" powered radios like the DX398 come along, so I use LM117 to reduce the voltage. When ever I can I build the regulator in the device. I added several "cigerette lighter" sockets because it is handy to be able to power up things like cell phone chargers froma clan DC source. I also added a 20 Amp mag breaker, both + and - to switch to an external power source like an automoble. Again this all sounds much fancier then it really is. Back in 1974 I learned to not depend on the public power company. The tornados that came through on April 3 that year knocked out power for several days. And my all of my radio gear required 120V AC. I decided then and there, sitting in the dark that the next time the lights went out I would still be able to listen. 31 years later I think I have suceeded fairly well. Terry |
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In article ,
Ron Hardin wrote: Snip The payoff is that the switching supplies generate much, much less heat, and thus use less power if left on all the time, in particular. Linear supplies are usually around 65% to 70% where switchers are often 80% to 90% range. -- Telamon Ventura, California |
Lucky wrote:
Hi Ron I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? Lucky --------------------------------------------- They may have improved swith mode power supplies in the last few years. But my experience has been that they produce a LOT of RF noise. Sinc ethe local RF noise almost always set the limits for reception, you can't receive singals lower then the locla noise floor, it is weel worth the erffort to keep my house as RF "clean" as I can. And using a switch mode to power my radio gear is at odds with receiving weak signals. I have friends who use switchnmode supplies, and mounted them in faraday cages with extensive fitlering for the AC mains and DC output. Even a well built linear/analog supply can need some additional bypass caps to really quiten it down. If I were going to use a switch mode, I would be sure to have an arrangement to retrun it if it was too noisy. Another point for me is linear supplies will last much longer due to their passive nature. Switch mode supplies have electronic switches, ether bipolar or FET transistors that fail with suprising regularitly. At the electronic facility where I work, we have linear supplies that are over 30 years old. None of the switchers last any where near that long. And anyone can repair a linear supply if it fails, switchmode supplies are much more complex and when they fail are very dificult to repair. Terry |
wrote in message ups.com... Lucky wrote: Hi Ron I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? Lucky --------------------------------------------- They may have improved swith mode power supplies in the last few years. But my experience has been that they produce a LOT of RF noise. Sinc ethe local RF noise almost always set the limits for reception, you can't receive singals lower then the locla noise floor, it is weel worth the erffort to keep my house as RF "clean" as I can. And using a switch mode to power my radio gear is at odds with receiving weak signals. I have friends who use switchnmode supplies, and mounted them in faraday cages with extensive fitlering for the AC mains and DC output. Even a well built linear/analog supply can need some additional bypass caps to really quiten it down. If I were going to use a switch mode, I would be sure to have an arrangement to retrun it if it was too noisy. Another point for me is linear supplies will last much longer due to their passive nature. Switch mode supplies have electronic switches, ether bipolar or FET transistors that fail with suprising regularitly. At the electronic facility where I work, we have linear supplies that are over 30 years old. None of the switchers last any where near that long. And anyone can repair a linear supply if it fails, switchmode supplies are much more complex and when they fail are very dificult to repair. Terry Good morning Terry. Based your real world experiences, it sounds better to stick with linear PSUs for now at least for me. I don't have the know how Ron has to make sure it all works right with a switching PSU if there is any added problems. I like to eliminate any potential problems that might occur if I have a choice. I just want to listen to the radio, not build faraday cages :) Lucky |
Lucky wrote:
wrote in message ups.com... Lucky wrote: Hi Ron I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? Lucky --------------------------------------------- They may have improved swith mode power supplies in the last few years. But my experience has been that they produce a LOT of RF noise. Sinc ethe local RF noise almost always set the limits for reception, you can't receive singals lower then the locla noise floor, it is weel worth the erffort to keep my house as RF "clean" as I can. And using a switch mode to power my radio gear is at odds with receiving weak signals. I have friends who use switchnmode supplies, and mounted them in faraday cages with extensive fitlering for the AC mains and DC output. Even a well built linear/analog supply can need some additional bypass caps to really quiten it down. If I were going to use a switch mode, I would be sure to have an arrangement to retrun it if it was too noisy. Another point for me is linear supplies will last much longer due to their passive nature. Switch mode supplies have electronic switches, ether bipolar or FET transistors that fail with suprising regularitly. At the electronic facility where I work, we have linear supplies that are over 30 years old. None of the switchers last any where near that long. And anyone can repair a linear supply if it fails, switchmode supplies are much more complex and when they fail are very dificult to repair. Terry Good morning Terry. Based your real world experiences, it sounds better to stick with linear PSUs for now at least for me. I don't have the know how Ron has to make sure it all works right with a switching PSU if there is any added problems. I like to eliminate any potential problems that might occur if I have a choice. I just want to listen to the radio, not build faraday cages :) Lucky Hi Lucky I have an Astron SS-30m. It's a switching power supply, and I've had no problems with RFI. I've never been fond of switching power supplies, but I'd read some good reviews, and decided the fact it's smaller and much lighter than a similarly rated linear supply made it worth a try. (I have a bad back) It was a good decision. I found it on ebay a couple years ago, new in box for roughly $100. I figure it'll handle just about anything I might need other than jump starting a car. They also make an SS20m. It probably would have met my needs, but the price on the larger one was right, and I figured extra capacity meant it would probably run cooler and last longer. I've yet to notice mine running above room temperature. Regards, Mark |
"Mark S. Holden" wrote: Lucky wrote: wrote in message ups.com... Lucky wrote: Hi Ron I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? Lucky --------------------------------------------- They may have improved swith mode power supplies in the last few years. But my experience has been that they produce a LOT of RF noise. Sinc ethe local RF noise almost always set the limits for reception, you can't receive singals lower then the locla noise floor, it is weel worth the erffort to keep my house as RF "clean" as I can. And using a switch mode to power my radio gear is at odds with receiving weak signals. I have friends who use switchnmode supplies, and mounted them in faraday cages with extensive fitlering for the AC mains and DC output. Even a well built linear/analog supply can need some additional bypass caps to really quiten it down. If I were going to use a switch mode, I would be sure to have an arrangement to retrun it if it was too noisy. Another point for me is linear supplies will last much longer due to their passive nature. Switch mode supplies have electronic switches, ether bipolar or FET transistors that fail with suprising regularitly. At the electronic facility where I work, we have linear supplies that are over 30 years old. None of the switchers last any where near that long. And anyone can repair a linear supply if it fails, switchmode supplies are much more complex and when they fail are very dificult to repair. Terry Good morning Terry. Based your real world experiences, it sounds better to stick with linear PSUs for now at least for me. I don't have the know how Ron has to make sure it all works right with a switching PSU if there is any added problems. I like to eliminate any potential problems that might occur if I have a choice. I just want to listen to the radio, not build faraday cages :) Lucky Hi Lucky I have an Astron SS-30m. It's a switching power supply, and I've had no problems with RFI. I've never been fond of switching power supplies, but I'd read some good reviews, and decided the fact it's smaller and much lighter than a similarly rated linear supply made it worth a try. (I have a bad back) It was a good decision. I found it on ebay a couple years ago, new in box for roughly $100. I figure it'll handle just about anything I might need other than jump starting a car. They also make an SS20m. It probably would have met my needs, but the price on the larger one was right, and I figured extra capacity meant it would probably run cooler and last longer. I've yet to notice mine running above room temperature. I currently run an RS-20M here, generally used as a power supply for my R7 though used on occassion for some two meter gear. At one time I had an RS-50M as I was running about 170 Watts on two meter sideband and CW. dxAce Michigan USA |
"Mark S. Holden" wrote in message ... Lucky wrote: wrote in message ups.com... Lucky wrote: Hi Ron I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? Lucky --------------------------------------------- They may have improved swith mode power supplies in the last few years. But my experience has been that they produce a LOT of RF noise. Sinc ethe local RF noise almost always set the limits for reception, you can't receive singals lower then the locla noise floor, it is weel worth the erffort to keep my house as RF "clean" as I can. And using a switch mode to power my radio gear is at odds with receiving weak signals. I have friends who use switchnmode supplies, and mounted them in faraday cages with extensive fitlering for the AC mains and DC output. Even a well built linear/analog supply can need some additional bypass caps to really quiten it down. If I were going to use a switch mode, I would be sure to have an arrangement to retrun it if it was too noisy. Another point for me is linear supplies will last much longer due to their passive nature. Switch mode supplies have electronic switches, ether bipolar or FET transistors that fail with suprising regularitly. At the electronic facility where I work, we have linear supplies that are over 30 years old. None of the switchers last any where near that long. And anyone can repair a linear supply if it fails, switchmode supplies are much more complex and when they fail are very dificult to repair. Terry Good morning Terry. Based your real world experiences, it sounds better to stick with linear PSUs for now at least for me. I don't have the know how Ron has to make sure it all works right with a switching PSU if there is any added problems. I like to eliminate any potential problems that might occur if I have a choice. I just want to listen to the radio, not build faraday cages :) Lucky Hi Lucky I have an Astron SS-30m. It's a switching power supply, and I've had no problems with RFI. I've never been fond of switching power supplies, but I'd read some good reviews, and decided the fact it's smaller and much lighter than a similarly rated linear supply made it worth a try. (I have a bad back) It was a good decision. I found it on ebay a couple years ago, new in box for roughly $100. I figure it'll handle just about anything I might need other than jump starting a car. They also make an SS20m. It probably would have met my needs, but the price on the larger one was right, and I figured extra capacity meant it would probably run cooler and last longer. I've yet to notice mine running above room temperature. Regards, Mark It's Mark! Hi there. Hope things are going well for you. Hey, I have a bad back too unfortunately. Can't really do anything for many bad backs except meds. Most of the ones on Ebay are your RS or SL models. Mainly linear supplies. Plus, I'm not looking to drop more then $50 on one really. So for me right now I'll just go with any good deal. I saw a couple switchers last week though. Does anyone know if Motorola makes a couple models for Astron? I see two or so Astrons on Ebay that are also refered to as "This Astron model is also Motorola part #1394A" and other part numbers. I saw one vendor who sold all Motorola equipment but he had 2 of the Astron's that were mentioned with Motorola in some Ebay ads. They had Astron's name on them but funny a Motorola dealer has them as part of his inventory. Anyone know anything? {about the PSU's :) :) Good to hear from you Mark. It's always a pleasure reading your comments. Hope our backs feel better. Thanks Lucky |
"Ron Hardin" wrote in message ... Lucky wrote: I heard switching supplies are not the best choice for radios. But I don't know enough about them to really know. So you're putting fuses on the hot wire {+}coming off the PSU to the radio?? I put a fuse on the hot wire, with amps based on the carrying capacity of the wire (not the capacity of the power supply!). The wire goes upstairs from the basement, and at the upstairs end I run it into many fuse blocks, each with tiny fuses (1/4 to 2a) for each of the devices I power with it, depending on its needs. The wires that typically run into coaxial power plugs have very little capacity before overheating, and you want its fuse to blow before it (the particular wire) heats up. So no short anywhere heats up any wire. A normally functioning power supply is quite capable of burning down the house if run into typical hookup wire without some fusing. It's unintuitive because the same wire works fine at 120v, but it's amps that causes heating, not power, and there's ten times more amps (=100 times more heating) at 12v than 120v. -- Ron Hardin On the internet, nobody knows you're a jerk. Ron, what capacity fuse should I buy for the usual wires that come with the power adapter tips at Radio Shack if I want to "Hot Guard" the output wires to power radios like you did? How can I find out it's carrying capacity? Is 1/4 A good? I think they sell wires with fuse holdes on them right? Thanks Lucky |
Lucky wrote:
It's Mark! Hi there. Hope things are going well for you. Hey, I have a bad back too unfortunately. Can't really do anything for many bad backs except meds. I've been quite busy lately with various things including the new telescope, and I've taken on another volunteer gig teaching astronomy to four classes of 8th graders at an inner city school. Most of the ones on Ebay are your RS or SL models. Mainly linear supplies. Plus, I'm not looking to drop more then $50 on one really. So for me right now I'll just go with any good deal. I saw a couple switchers last week though. I still like linear supplies - mostly because I can usually figure out how to fix them if they break. A nice thing about ebay is odds are another one will turn up in a week or two. snip Good to hear from you Mark. It's always a pleasure reading your comments. Hope our backs feel better. Actually, I've got my back pretty well under control, but it took some lifestyle changes, replacing my mattresses and just about every chair I normally sit on. If you contact me direct I may be able to give you some pointers on your back. Regards, Mark Thanks Lucky |
Lucky wrote:
Ron, what capacity fuse should I buy for the usual wires that come with the power adapter tips at Radio Shack if I want to "Hot Guard" the output wires to power radios like you did? How can I find out it's carrying capacity? Is 1/4 A good? I think they sell wires with fuse holdes on them right? I fuse the individual device wires for the device's claimed needs, more or less times two. If it says 500ma, use a 1a (quick blow) fuse. I got a bunch of 6-fuse fuse blocks (automotive, I guess) and wire all of one side to +12v, and attach the device + wires to the other side. Radio Shack has 4-fuse blocks. I'd really like 20-fuse blocks already wired together on one side but haven't found any. The 16ga zipcord is fused with an inline fuse (quick blow) at I think 7a. Use quick-blow fuses because slow-blow fuses get very hot themselves without blowing. If a device blows a fuse in normal use, just use the next size bigger fuse. Acc. to what I can find on the web, 16ga wire is good for 10a, or 13a, depending on who you believe, and also that's an AC rating and who knows what that means at DC. Anyway somebody believes that's acceptable heating. Every 3 wire gauges thinner gives you 2x the heating. -- Ron Hardin On the internet, nobody knows you're a jerk. |
wrote in message oups.com... "Lucky" Wrote (in part): Does anyone know if Motorola makes a couple models for Astron? I see two or so Astrons on Ebay that are also refered to as "This Astron model is also Motorola part #1394A" and other part numbers. I saw one vendor who sold all Motorola equipment but he had 2 of the Astron's that were mentioned with Motorola in some Ebay ads. They had Astron's name on them but funny a Motorola dealer has them as part of his inventory. Anyone know anything? {about the PSU's :) :) snip Thanks Lucky ------------------------------ You have it backwards, Astron makes(?made?) them for Motorola. They are just as good as normal Astrons. Terry Yes Terry that Motorola dealer wrote me and told me that also. BTW, I finally bought a "new in Box" Astron SL-11a for $45 off Ebay. Looks good and I think 7 Amps Cont. is enough for me right now. What do you guys think of it? Lucky |
Lucky wrote:
wrote in message oups.com... "Lucky" Wrote (in part): Does anyone know if Motorola makes a couple models for Astron? I see two or so Astrons on Ebay that are also refered to as "This Astron model is also Motorola part #1394A" and other part numbers. I saw one vendor who sold all Motorola equipment but he had 2 of the Astron's that were mentioned with Motorola in some Ebay ads. They had Astron's name on them but funny a Motorola dealer has them as part of his inventory. Anyone know anything? {about the PSU's :) :) snip Thanks Lucky ------------------------------ You have it backwards, Astron makes(?made?) them for Motorola. They are just as good as normal Astrons. Terry Yes Terry that Motorola dealer wrote me and told me that also. BTW, I finally bought a "new in Box" Astron SL-11a for $45 off Ebay. Looks good and I think 7 Amps Cont. is enough for me right now. What do you guys think of it? Lucky Personally, I'd rather have one with meters, but 7 amps is probably more than enough unless you're looking to run several receivers at once or take up arc welding as a hobby. Otherwise, as far as I know, Astron has a reputation for making good quality power supplies. |
Lucky wrote: Yes Terry that Motorola dealer wrote me and told me that also. BTW, I finally bought a "new in Box" Astron SL-11a for $45 off Ebay. Looks good and I think 7 Amps Cont. is enough for me right now. What do you guys think of it? Lucky It will serve you well for decades. I am not a big fan of MOV over voltage protectors, but it might be well worth the few dollars it will take to add on between the Astron and the wall outlet. Terry |
All of the Astron supplies that Ihave sen have the power switch in the
primary,so when it it turned off there is no current being drawn. In my situation I have radios that stay on all f the time, so my power supply is almost never switched off. Lambda supplies don't have a pwoer switch so I have to unplug them to turn them off. Thenice thing about a MOV or other over voltage protector, is it will help tostop any line spikes from getting tot he power supply. I use a non MOV style,a Zero Surge, but MOV based units are much more common and can realy save you supply. I have my "radio desk", a PC "L" desk in fact, wired with a DPDT magnetic breaker so I can flip one "switch" and remove connection with both sides of the AC mains. I have another breaker for the standby gell cells so so with one hand I can knock my entire system down. Likely over kill, but I wanted something that was easy and fast to kill all power in case something goes wrong. Terry |
First appreciate what the MOVs do. A transient coming down
black wire is shunted by MOV to all other wires. Now a transient, seeking earth ground, has more paths to find earth, destructively, via the adjacent appliance. Protection is located in earthing; not inside a plug-in protector. An MOV is effective if connected short from each utility wire to earth ground. This is why 'whole house' protectors are so effective and why plug-in protectors can even contribute to damage of the adjacent appliance. These concepts are often discussed in the newsgroup rec.radio.amateur.antenna. Some protection systems use MOVs. Some require no MOVs. But in every protection 'system', only one component that is always required. Earth ground. Plug-in protector have no such earthing connection - so they avoid the entire topic. Plug-in protector provide no effective protection, so are even undersized - too few joules sold overpriced. MOVs are shunt mode protectors. Another type is series mode. Series mode protectors will supplement a protection 'system'. A series mode protector alone must stop, block, or absorb what three miles of sky could not. Will not happen. Series mode protectors alone must act like a dam. Insufficient. Series mode protectors used in conjunction with a 'whole house' protector will act like a dike. Now we are talking effective protection. Series mode protectors are sold by Zerosurge, Surgex, and Brickwall. They can supplement the primary and secondary protection 'systems'. Notice that safety ground wire that bypasses a series mode protector. So the Zerosurge, et al block a black (hot) or white (neutral) wire transient that simply enters electronics via the direct green (safety ground) wire. Where is the protection? Just another reason why series mode protectors can only be part of a protection 'system'. 'Whole house' protectors being so inexpensive and so effective that the telco even installs one on your incoming telephone line - for free. Notice what that telco protector connects to? Earth ground. A protector is only as effective as its earth ground. Lucky wrote: wrote in message oups.com... I am not a big fan of MOV over voltage protectors, but it might be well worth the few dollars it will take to add on between the Astron and the wall outlet. Terry Hi Terry I was wondering about that. I've been using a surge protector all this time. Can't hurt to plug the Astron into it right? With wall worts and other radio PSU's, they tell you to unplug them so they last longer. I mean they still are warm even if the radio is turned off. Does it work that way with the Astrons? Even if you turn it off it's still drawing some current and stays warm to some degree? Should I turn off the surge protector or unplug it when not in use? Lucky |
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