Home |
Search |
Today's Posts |
#31
|
|||
|
|||
On Sun, 5 Oct 2003 20:58:04 +0200, "Thierry"
wrote: "Dave Holford" wrote in message .. . ... Thierry wrote: Just out of curiosity - all these measurements used the same power meter? Yes of course. What meter are you using? Brand and model number? Is it measuring "average" power -- or "peak PEP" power? Bob k5qwg I don't recall ever seeing 100W on SSB with my TS-430, TS-440 or TS-570 when speaking, a steady tone will do it of course. Hi, This is the first time that we note this problem too and the problem was detected by chance... :-(( All users are exprimented OM some for decades and never observe this effect... All told me that indeed their TX cannot emit its full power in SSB but rather 50-60% in speaking normally. So we were very surprised than one of us could reach the full power... Our friend used a TS-840S and some olders and show us at the radioclub what the matter with its TX. He nearly reaches and sometimes exceed the 100W...in SSB, something we even can't get using a yaesu 1000 MP of the last generation ! So as he recently bought the new TS570D he immediately noticed the difference. Even using an electret microphone (using a battery and known to boost emissions much more than a dynamic one) he cannot get the full power of its older TX. Therefore we did some complementary measurements and have searched for some information. Hence this post and some others So at first sight I suspected an error in its reading procedure, etc. But not at all... Someone having read my TS570D review on Internet explained me that he knew the problem and how to solve it. I am waiting now more detail (how to increase the signal and what about QRM, etc). Thierry Dave |
#32
|
|||
|
|||
"Dave Holford" wrote in message ... Thierry wrote: Just out of curiosity - all these measurements used the same power meter? Two external wattmeters where used. One is an old one from Yaesu called YS 2000 max reading 2000 W and we selected both RMS then PEP with a switch. The other one is a more recent of my friend. I have not its specs for the moment. Thierry I don't recall ever seeing 100W on SSB with my TS-430, TS-440 or TS-570 when speaking, a steady tone will do it of course. I confirm, hence the "misunderstanding" we all had when our friend told us that he can get 100W in SSB... Thierry Dave |
#33
|
|||
|
|||
"Dave Holford" wrote in message ... Thierry wrote: Just out of curiosity - all these measurements used the same power meter? Two external wattmeters where used. One is an old one from Yaesu called YS 2000 max reading 2000 W and we selected both RMS then PEP with a switch. The other one is a more recent of my friend. I have not its specs for the moment. Thierry I don't recall ever seeing 100W on SSB with my TS-430, TS-440 or TS-570 when speaking, a steady tone will do it of course. I confirm, hence the "misunderstanding" we all had when our friend told us that he can get 100W in SSB... Thierry Dave |
#34
|
|||
|
|||
"Thierry" wrote in message ... "Ed G." wrote in message . .. Question for Thierry: Can I assume you have a "Peak" reading wattmeter? Otherwise, you are aware, I hope, that most wattmeters are "average" power reading and that they can not display the peak readings of a SSB transmitted signal.... thus they will never display close to the 100watts of a 100watt rated SSB signal; unless you are modulating the transmitter with a test tone audio source. Hi Ed, Yes for sure. But I think that it rather displays the "instantaneous" modulation not an average because when I shout at the mic or using the key the nidddle reaches immediately the maximum without delay and speaking normally I emit about 40-60 watts only, moving up and down at the rate of my words. That would be the correct reading. 60W is perhaps a bit high, but if you have the compressor turned on you might get 60W average. Usual peak to average for SSB is a factor of two or even three. -- ... Hank Hank: http://horedson.home.att.net W0RLI: http://w0rli.home.att.net |
#35
|
|||
|
|||
"Thierry" wrote in message ... "Ed G." wrote in message . .. Question for Thierry: Can I assume you have a "Peak" reading wattmeter? Otherwise, you are aware, I hope, that most wattmeters are "average" power reading and that they can not display the peak readings of a SSB transmitted signal.... thus they will never display close to the 100watts of a 100watt rated SSB signal; unless you are modulating the transmitter with a test tone audio source. Hi Ed, Yes for sure. But I think that it rather displays the "instantaneous" modulation not an average because when I shout at the mic or using the key the nidddle reaches immediately the maximum without delay and speaking normally I emit about 40-60 watts only, moving up and down at the rate of my words. That would be the correct reading. 60W is perhaps a bit high, but if you have the compressor turned on you might get 60W average. Usual peak to average for SSB is a factor of two or even three. -- ... Hank Hank: http://horedson.home.att.net W0RLI: http://w0rli.home.att.net |
#36
|
|||
|
|||
I am agree of course with your opinion.
If I follow strictly my idea my 570 will stay like it is, and until know I have not made the modification (For the ones who are interested in this mod I can send you the 2 JPG as attachment. This fix is easy you only need a special cable to plug your mic in the accessory plug if you want to preserve your default mic socket). This is mainly my friend Al who want this mod because is older TS840S is better excited and he wants to find again this power on his new rig 570 to recah pileups, he says. Personally, as I have told the mod is not really necessary for me as I can use a linear if needed (although I use it very few excepting at night of during very bad propa). But sometimes I cannot drive my amplifier due the loss of power, my linear requesting at least 80W input to produce up to 2 kW (that I never use, as usually I work at 500-800W output using the beam, never more). I retain also your comments about passive and active peak meters for the next time. My old Yaesu YS 2000 wattmeter has to be replaced by a more recent model and both reading, RMS and peak I have on my wattmeter, will be necessary on my new one too. Thierry ON4SKY, LX3SKY "Mark Keith" wrote in message om... "Thierry" wrote in message ... Hi, If you have an external wattmeter connected to your transmitter, can you make a test at 100 Watts PEP and give me your true emitting power in watts ? Speaking normally (without shouting) in their mike with normal compression (10 over 25), some hams say that their wattmeter displays a power of about 50-60 watts (of course in CW they reach 100 W) But some arrive to move the niddle to about 100 watts in SSB using their barefoot RTX... This could be all over the map, depending on the type of wattmeter used. Very few wattmeters are good at giving an accurate reading of voice peaks. The meter movements are too slow. If someone see's the full 100w on SSB, they either have an excellent peak reading wattmeter, or they are overdriving their radio. I'd say the majority #2...:/ It seems that some RTX can reach the nominal power doing a hardware modification at the mike itself to increase the 60 w displayed in SSB to about 100W. According these hams there is no disadvantage to make this change. There is no advantage either, if the mike circuit is capable of fully driving the radio. The circuit you have is surely capable. All you will end up doing is adding distortion, and lowering the setting you keep your mike gain. The problem mainly occurs of the Kenwood TS-570D (all the serie in fact) using a handy mic or even a desk model (the ones sold by Kenwood). The same problem occurs with the Yaesu 1000 MP (tested at 100 W). I've never heard of any such problem. You are just being fooled by the meter. Didn't this type thing come up a few weeks ago? You have average reading meters, and you have type of peak reading meters. With NORMAL drive, and average speach, you will usually see only 25-35 watts on an average meter when doing 100w out. This is normal!!! Don't try to pump up the gain to get more reading. You will just overdrive. Then you have passive peak reading meters. They are always sluggish, and never read the full actual output. Most will average about 80w peaks, with actual 100w peaks. All they are doing is adding a small electrolytic cap to the meters to give some "hang time". Then you have active peak reading meters. These will be the most accurate, but still can't be taken as gospel as voice patterns vary. If you can adjust your mike gain and be within the normal ALC specs for that radio, you have enough mike drive. If you can whistle hard into the mike, and get nearly 100w on the meter, you have enough mike drive. Don't worry about what you read on SSB. If you are doing 100w CW, you should be doing it on SSB. Heck, When I run 1300w out, I usually see only about 400w on average meter voice peaks. Don't think my voice peaks are really 1300w? Go out and grab the end of my antenna, and get back to me after the paramedics wake you up. :/ The bottom line. Very, very few wattmeters are worth a hoot at measuring SSB voice peaks. You are worrying about an issue that doesn't really exist. Well, unless the rare case you do have a radio problem, but I doubt it. A friend of mine runs a 570, and he's made no mention of this "problem". Misunderstanding wattmeter action is very common among newer hams. Thats why many overdrive, when they really are not intending to. They are fooled by those dang blasted meters. MK |
#37
|
|||
|
|||
I am agree of course with your opinion.
If I follow strictly my idea my 570 will stay like it is, and until know I have not made the modification (For the ones who are interested in this mod I can send you the 2 JPG as attachment. This fix is easy you only need a special cable to plug your mic in the accessory plug if you want to preserve your default mic socket). This is mainly my friend Al who want this mod because is older TS840S is better excited and he wants to find again this power on his new rig 570 to recah pileups, he says. Personally, as I have told the mod is not really necessary for me as I can use a linear if needed (although I use it very few excepting at night of during very bad propa). But sometimes I cannot drive my amplifier due the loss of power, my linear requesting at least 80W input to produce up to 2 kW (that I never use, as usually I work at 500-800W output using the beam, never more). I retain also your comments about passive and active peak meters for the next time. My old Yaesu YS 2000 wattmeter has to be replaced by a more recent model and both reading, RMS and peak I have on my wattmeter, will be necessary on my new one too. Thierry ON4SKY, LX3SKY "Mark Keith" wrote in message om... "Thierry" wrote in message ... Hi, If you have an external wattmeter connected to your transmitter, can you make a test at 100 Watts PEP and give me your true emitting power in watts ? Speaking normally (without shouting) in their mike with normal compression (10 over 25), some hams say that their wattmeter displays a power of about 50-60 watts (of course in CW they reach 100 W) But some arrive to move the niddle to about 100 watts in SSB using their barefoot RTX... This could be all over the map, depending on the type of wattmeter used. Very few wattmeters are good at giving an accurate reading of voice peaks. The meter movements are too slow. If someone see's the full 100w on SSB, they either have an excellent peak reading wattmeter, or they are overdriving their radio. I'd say the majority #2...:/ It seems that some RTX can reach the nominal power doing a hardware modification at the mike itself to increase the 60 w displayed in SSB to about 100W. According these hams there is no disadvantage to make this change. There is no advantage either, if the mike circuit is capable of fully driving the radio. The circuit you have is surely capable. All you will end up doing is adding distortion, and lowering the setting you keep your mike gain. The problem mainly occurs of the Kenwood TS-570D (all the serie in fact) using a handy mic or even a desk model (the ones sold by Kenwood). The same problem occurs with the Yaesu 1000 MP (tested at 100 W). I've never heard of any such problem. You are just being fooled by the meter. Didn't this type thing come up a few weeks ago? You have average reading meters, and you have type of peak reading meters. With NORMAL drive, and average speach, you will usually see only 25-35 watts on an average meter when doing 100w out. This is normal!!! Don't try to pump up the gain to get more reading. You will just overdrive. Then you have passive peak reading meters. They are always sluggish, and never read the full actual output. Most will average about 80w peaks, with actual 100w peaks. All they are doing is adding a small electrolytic cap to the meters to give some "hang time". Then you have active peak reading meters. These will be the most accurate, but still can't be taken as gospel as voice patterns vary. If you can adjust your mike gain and be within the normal ALC specs for that radio, you have enough mike drive. If you can whistle hard into the mike, and get nearly 100w on the meter, you have enough mike drive. Don't worry about what you read on SSB. If you are doing 100w CW, you should be doing it on SSB. Heck, When I run 1300w out, I usually see only about 400w on average meter voice peaks. Don't think my voice peaks are really 1300w? Go out and grab the end of my antenna, and get back to me after the paramedics wake you up. :/ The bottom line. Very, very few wattmeters are worth a hoot at measuring SSB voice peaks. You are worrying about an issue that doesn't really exist. Well, unless the rare case you do have a radio problem, but I doubt it. A friend of mine runs a 570, and he's made no mention of this "problem". Misunderstanding wattmeter action is very common among newer hams. Thats why many overdrive, when they really are not intending to. They are fooled by those dang blasted meters. MK |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Wanted: Power Supply for TR-4C | Boatanchors | |||
Wanted: Power Supply for TR-4C | Boatanchors | |||
Derivation of the Reflection Coefficient? | Antenna | |||
Length of Coax Affecting Incident Power to Meter? | Antenna |