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HQ180A restore
hi guys,
i am restoring an hq180a. been a while since i messed with tubes, (abt 20 yrs) am in need of a little direction. i checked & replaced bad tubes, verified b+ v. 2 problems, may be related??? on top band, very poor reception, & when u adj ant. control, u hit a spot that causes oscellation or motorboating. prob #2...on top 2 bands, cw sigs have a raspy note. not t9 at all. it is a high s/n rcvr 6377. kind of neat, has spinner knobs, noise blanker, & 455 kc if brought out to rear apron. i guess previous owner did mod, but it sure looks factory....solder connections, etc. would appreciate any and all guesses. tnx, pete, k2iqk |
HQ180A restore
On Feb 2, 11:43�pm, wrote:
� � �hi guys, � � �i am restoring an hq180a. �been a while since i messed with tubes, (abt 20 yrs) am in need of a little direction. �i checked �& replaced bad tubes, verified b+ v. �2 problems, may be related??? on top band, very poor reception, & when u adj ant. control, u hit a spot that causes oscellation or motorboating. �prob #2...on top 2 bands, cw sigs have a raspy note. �not t9 at all. �it is a high s/n rcvr 6377. �kind of neat, has spinner knobs, noise blanker, & 455 kc if brought out to rear apron. �i guess previous owner did mod, but it sure looks factory....solder connections, etc. � � �would appreciate any and all guesses. � � �tnx, pete, k2iqk hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. 73, pete |
HQ180A restore
wrote in message ... On Feb 2, 11:43�pm, wrote: � � �hi guys, � � �i am restoring an hq180a. �been a while since i messed with tubes, (abt 20 yrs) am in need of a little direction. �i checked �& replaced bad tubes, verified b+ v. �2 problems, may be related??? on top band, very poor reception, & when u adj ant. control, u hit a spot that causes oscellation or motorboating. �prob #2...on top 2 bands, cw sigs have a raspy note. �not t9 at all. �it is a high s/n rcvr 6377. �kind of neat, has spinner knobs, noise blanker, & 455 kc if brought out to rear apron. �i guess previous owner did mod, but it sure looks factory....solder connections, etc. � � �would appreciate any and all guesses. � � �tnx, pete, k2iqk hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. 73, pete Again, I suspect the problem is bad capacitors. Tunable hum is typical of feedback allowed by bad power supply decoupling caps as is oscillation. I doubt if alignment has anything to do with it. Finding the bad caps may be a lot of work but you can at isolate them to a particular stage of the RX. I don't know what kind of caps Hammarlund was using when the HQ 180 was made. They evidently learned about Black Beauty paper caps from the SP-600 and may have switched to ceramics. If so the chances of bad ones is pretty small but even ceramic caps don't last forever. A capacitor checker would be very helpful. -- --- Richard Knoppow Los Angeles, CA, USA |
HQ180A restore
wrote in message ... On Feb 2, 11:43�pm, wrote: � � �hi guys, � � �i am restoring an hq180a. �been a while since i messed with tubes, (abt 20 yrs) am in need of a little direction. �i checked �& replaced bad tubes, verified b+ v. �2 problems, may be related??? on top band, very poor reception, & when u adj ant. control, u hit a spot that causes oscellation or motorboating. �prob #2...on top 2 bands, cw sigs have a raspy note. �not t9 at all. �it is a high s/n rcvr 6377. �kind of neat, has spinner knobs, noise blanker, & 455 kc if brought out to rear apron. �i guess previous owner did mod, but it sure looks factory....solder connections, etc. � � �would appreciate any and all guesses. � � �tnx, pete, k2iqk hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. 73, pete I should have added to watch out for the power supply filter caps also. Bad caps could account for the hum and rough CW notes plus allow some feedback through the power supply although at RF the by-pass and decoupling caps should prevent that. Try the power supply filter caps first. -- --- Richard Knoppow Los Angeles, CA, USA |
HQ180A restore
Don't mess with the alignment yet! If you don't have a well
calibrated signal generator (a frequency counter to go with it would be better) you will probably just screw up the IF alignment. It is important to get the third if aligned to exactly 60 kHz for the sideband selector function to work properly. You will need a sweep generator to properly align the first (3035 kHz) IF. The IF alignment is unlikely to be the problem with the oscillation. Only attempt the IF alignment if you have the proper equipment and know how to use it. If the alignment hasn't been messed with, it is probably OK. Make sure all tube shields are in place and all the bypass capacitors are good. The HQ-180 uses mostly ceramic caps, but as mentioned, they can be bad. Replace the filter caps first, then go from there. --Ed |
HQ180A restore
wrote:
hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
HQ180A restore
"Scott Dorsey" wrote in message ... wrote: hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott Is there anyone who does front panels for the HQ180 ? I have one in excellent condition except the front panel is quite rusty and unreadable. -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
HQ180A restore
Scott Dorsey wrote:
wrote: hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott That's kind of like looking for when Bush is lying...it's when his lips are moving. How do you know if they're leaking? They're the paper ones--they all leak...or will. jak |
HQ180A restore
jakdedert wrote:
Scott Dorsey wrote: wrote: hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott That's kind of like looking for when Bush is lying...it's when his lips are moving. How do you know if they're leaking? They're the paper ones--they all leak...or will. jak I sure am glad you could clarify that. HQ-180A's don't have paper caps. |
HQ180A restore
"jakdedert" wrote in message .. . Scott Dorsey wrote: wrote: hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott That's kind of like looking for when Bush is lying...it's when his lips are moving. How do you know if they're leaking? They're the paper ones--they all leak...or will. jak You need a capacitance bridge to measure the dissipation factor. The by-pass and decoupling caps in the HQ-180 appear to be mostly disc ceramic caps. These have relatively low dissipation factor and are considered quite reliable but can go bad. Electrolytic caps, mostly used for power supply filter caps, at least in vacuum tube equipment, have relatively high dissipation factors when new but mainly fail when not used for some time. One plate of the capacitor is s chemical film which depends on the presense of a voltage to form so if not used for some time the thing simply stops being a capacitor. Paper caps can actually be pretty good. If reasonably well sealed they have long lives. The notorious Black Beauty caps, as used in Hammarlund SP-600-JX receivers, had a manufacturing problem which caused them to be short lived. Actually, they were intended and sold to be long lived high performance caps and are found in all sorts of very high quality equipment. I suspect that moisture getting into the caps is the main cause of failures but they started getting a bad reputation not long after they began to be used so it might be something else. Good paper type caps should have dissipation factors (at 1 khz) on the order of 0.01 or less and very low leakage types like ceramic, silver mica, and plastic (polyethylene, etc.) of perhaps 1/10th of this. Electrolytic caps will have dissipation factors much larger, however, they really should be measured with DC on them and some capacitor checkers allow for this. My bet about the HQ-180 is that the power supply filter caps are sick. -- --- Richard Knoppow Los Angeles, CA, USA |
HQ180A restore
wrote:
hi guys, i am restoring an hq180a. been a while since i messed with tubes, (abt 20 yrs) am in need of a little direction. i checked & replaced bad tubes, verified b+ v. 2 problems, may be related??? on top band, very poor reception, & when u adj ant. control, u hit a spot that causes oscellation or motorboating. prob #2...on top 2 bands, cw sigs have a raspy note. not t9 at all. it is a high s/n rcvr 6377. kind of neat, has spinner knobs, noise blanker, & 455 kc if brought out to rear apron. i guess previous owner did mod, but it sure looks factory....solder connections, etc. would appreciate any and all guesses. tnx, pete, k2iqk Regarding front panels... Dee W4PNT (Patty and Dee's Marine) does the 180A panel. He's the guy who also does Valiants and Rangers. http://w4pnt.8k.com Regards de K3HVG |
HQ180A restore
"K3HVG" wrote in message . .. wrote: hi guys, i am restoring an hq180a. been a while since i messed with tubes, (abt 20 yrs) am in need of a little direction. i checked & replaced bad tubes, verified b+ v. 2 problems, may be related??? on top band, very poor reception, & when u adj ant. control, u hit a spot that causes oscellation or motorboating. prob #2...on top 2 bands, cw sigs have a raspy note. not t9 at all. it is a high s/n rcvr 6377. kind of neat, has spinner knobs, noise blanker, & 455 kc if brought out to rear apron. i guess previous owner did mod, but it sure looks factory....solder connections, etc. would appreciate any and all guesses. tnx, pete, k2iqk Regarding front panels... Dee W4PNT (Patty and Dee's Marine) does the 180A panel. He's the guy who also does Valiants and Rangers. http://w4pnt.8k.com This website shows the last update of Sept 2005. At that time they were not going to do ant more painting. Regards de K3HVG |
HQ180A restore
Richard Knoppow wrote:
"jakdedert" wrote in message .. . Scott Dorsey wrote: wrote: hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott That's kind of like looking for when Bush is lying...it's when his lips are moving. How do you know if they're leaking? They're the paper ones--they all leak...or will. jak You need a capacitance bridge to measure the dissipation factor. The by-pass and decoupling caps in the HQ-180 appear to be mostly disc ceramic caps. These have relatively low dissipation factor and are considered quite reliable but can go bad. Electrolytic caps, mostly used for power supply filter caps, at least in vacuum tube equipment, have relatively high dissipation factors when new but mainly fail when not used for some time. One plate of the capacitor is s chemical film which depends on the presense of a voltage to form so if not used for some time the thing simply stops being a capacitor. Good info which explains 'why' old electro's should simply be replaced. Paper caps can actually be pretty good. If reasonably well sealed they have long lives. The notorious Black Beauty caps, as used in Hammarlund SP-600-JX receivers, had a manufacturing problem which caused them to be short lived. Actually, they were intended and sold to be long lived high performance caps and are found in all sorts of very high quality equipment. I suspect that moisture getting into the caps is the main cause of failures but they started getting a bad reputation not long after they began to be used so it might be something else. I've read that the paper was not all that high quality...contains acids which will inevitably break it down. Moisture is the main culprit, but only leads to breakdown sooner than later. Wax as a sealer was never going to have as long life as the other parts of the electronics in which these were installed. Good paper type caps should have dissipation factors (at 1 khz) on the order of 0.01 or less and very low leakage types like ceramic, silver mica, and plastic (polyethylene, etc.) of perhaps 1/10th of this. Electrolytic caps will have dissipation factors much larger, however, they really should be measured with DC on them and some capacitor checkers allow for this. Conventional wisdom is that they'll leak sooner or later anyway. Better to shotgun them and be done with it. The wax will likely melt sooner or later, anyway. OTOH, Chuck says there are no paper caps in the 180, so I'd defer to that. My bet about the HQ-180 is that the power supply filter caps are sick. ....and should be replaced. If they're not sick now, they could fail in spectacular (or not) fashion down the line. It's about the easiest thing to do...replace the filters. If they're not bad now, it's just one less thing to worry about. I operate some vintage tube gear in which I've not replaced the filters; but I realize I'm sitting on a potential time bomb. First sign of a hum, I'm turning power off...which might be too late. Just because I don't follow my own advice (all the time) doesn't make it bad advice. jak |
HQ180A restore
"jakdedert" wrote in message . .. Richard Knoppow wrote: "jakdedert" wrote in message .. . Scott Dorsey wrote: wrote: hi again, tnx for the replies..i did clean all wafer sws & pots, didn't clean main tuning cap..have bama prints for rx..will try voltage & resistance checks..full alignment sounds like a good idea..i have sig gen..1st & 2nd ifs would be difficult because sig gen calib not great..i dont think if alignment is my main prob..but will do all hf aligns..i'm glad to get back into tubes..its like restoring a classic car, but alot cheaper...hi hi. tnx agn..if u have any more ideas, pse email me. Before you touch the alignment, look for leaky paper caps. --scott That's kind of like looking for when Bush is lying...it's when his lips are moving. How do you know if they're leaking? They're the paper ones--they all leak...or will. jak You need a capacitance bridge to measure the dissipation factor. The by-pass and decoupling caps in the HQ-180 appear to be mostly disc ceramic caps. These have relatively low dissipation factor and are considered quite reliable but can go bad. Electrolytic caps, mostly used for power supply filter caps, at least in vacuum tube equipment, have relatively high dissipation factors when new but mainly fail when not used for some time. One plate of the capacitor is s chemical film which depends on the presense of a voltage to form so if not used for some time the thing simply stops being a capacitor. Good info which explains 'why' old electro's should simply be replaced. Paper caps can actually be pretty good. If reasonably well sealed they have long lives. The notorious Black Beauty caps, as used in Hammarlund SP-600-JX receivers, had a manufacturing problem which caused them to be short lived. Actually, they were intended and sold to be long lived high performance caps and are found in all sorts of very high quality equipment. I suspect that moisture getting into the caps is the main cause of failures but they started getting a bad reputation not long after they began to be used so it might be something else. I've read that the paper was not all that high quality...contains acids which will inevitably break it down. Moisture is the main culprit, but only leads to breakdown sooner than later. Wax as a sealer was never going to have as long life as the other parts of the electronics in which these were installed. Good paper type caps should have dissipation factors (at 1 khz) on the order of 0.01 or less and very low leakage types like ceramic, silver mica, and plastic (polyethylene, etc.) of perhaps 1/10th of this. Electrolytic caps will have dissipation factors much larger, however, they really should be measured with DC on them and some capacitor checkers allow for this. Conventional wisdom is that they'll leak sooner or later anyway. Better to shotgun them and be done with it. The wax will likely melt sooner or later, anyway. OTOH, Chuck says there are no paper caps in the 180, so I'd defer to that. My bet about the HQ-180 is that the power supply filter caps are sick. ...and should be replaced. If they're not sick now, they could fail in spectacular (or not) fashion down the line. It's about the easiest thing to do...replace the filters. If they're not bad now, it's just one less thing to worry about. I operate some vintage tube gear in which I've not replaced the filters; but I realize I'm sitting on a potential time bomb. First sign of a hum, I'm turning power off...which might be too late. Just because I don't follow my own advice (all the time) doesn't make it bad advice. jak Electrolytics can have a very long life. Generally, they go bad slowly with an attendant drop in supply voltage and increase in hum. They rarely have catastrophic failures except after a long period of disuse when they become non-capacitors. Sometimes they can expode resulting in a bad smelling mess. This is pretty unusual. The power supply caps also act to by-pass some signals, especially audio, to ground. So one symptom of bad filter caps may be audio when the volume control is all the way down or noise or distortion. I would not replace good caps simply beause they are old. As long as they are being used the film which constitutes one plate, will stay formed. Occasionally something will cause a short but, again, thats not too common. Paper caps are all over the place. The old oil-filled ones were quite reliable and of high quality but were large. Most are high-voltage types. Unfortunately the dielectric oil used for many years turned out to be a form of PCB which is a cancer risk. These were sold with names like Pyranol, Dykanol, etc. Again, if you have some and they are not leaking, leave them alone. The main virtue of these oils was that they are not inflamable which was not true of the mineral and vegetable oils used previously. Some tubular caps used a wax impregnant as the dielectric. Some were simply wax covered. Keep in mind that the latest of these guys is probably getting on toward half a century so its not surprizing that there are failures. The Black Beauty caps found in a lot of 1950s equipment were intended to be deluxe, low leakage, long life types. For some reason they began to fail after only a few years. I think an improved version was made because some later equipment has caps that look the same but don't seem to fail early. Another type of capacitor was made by the same company under the name Orange Drop. These shared the same plastic impregnated paper dielectric but were equipped with dipped epoxy cases rather than the molded Bakelite cases of the Black Beauty types. Orange Drop caps seem to be quite reliable which leads me to think the problem wtih the BBs was the casing rather than some problem with the impregnant or paper. Of course, at this late date, I doubt if we will ever know. Hammarlund got burned badly with the BB's which had to be replaced in thousands of military receivers so I think they avoided them afterward. -- --- Richard Knoppow Los Angeles, CA, USA |
HQ180A restore
I just fixed up an HQ-145 of about the same vintage as the HQ-180 and
my canned electrolytics, a triple section capacitor containing the two power supply filters and an audio capacitor failed the "smoke" test. I recapped those three caps. I did save the can in case I ever want to reinstall modern caps inside the can, but that seemed like an awful lot of work when even the most ardent collectors acknowledge that capacitor substitution should be done anyway in the interest of safety. Since small radio parts failed even when new and parts replacement was a normal activity (that's why there were so many radio/TV repairment around...where have they gone?) I guess this sort of restoration isn't quite as anal retensive as restoring Corvettes. Jon Teske, W3JT |
HQ180A restore
Jon Teske ) writes:
I just fixed up an HQ-145 of about the same vintage as the HQ-180 and my canned electrolytics, a triple section capacitor containing the two power supply filters and an audio capacitor failed the "smoke" test. I recapped those three caps. I did save the can in case I ever want to reinstall modern caps inside the can, but that seemed like an awful lot of work when even the most ardent collectors acknowledge that capacitor substitution should be done anyway in the interest of safety. I thought a lot of "recap everything" was based on the assumption that some would fail, and once you're at it, you might as well do them all. This is especially significant in things that would actually classify as boatanchors, since getting them open can often require quite a bit of work. Once you've done that to fix that one capacitor embedded way down in layers of shielding, changing the other capacitors at the time hardly adds much time to the effort. But if you don't simply change all the capacitors at that time, you're doomed to going through the disassembly process at some later point. It actually seems to be the real collectors that drive the notion of keeping things intact. They want that original look, so they will stuff new capacitors in old cases, and print up new paper wrappers to put on new capacitors when that fits the situation. SOme will even decide that "keeping it original" is more important than using the thing, so they don't do anything to it, letting it sit on the shelf unused rather than do anything to it. But they are collecting, which is different from someone who wants an old radio to actually use. Michael VE2BVW |
HQ180A restore
You have made a good start by cleaning the controls and doing some voltage
checks. I would NOT try to align it at this stage. That's one of the last things likely to be a serious problem, unless somebody gave the receiver to a child with a screwdriver. I would definitely replace the electrolytic capacitors. They are the most failure-prone components in the radio. Until you are sure that the power supply is healthy, it's pointless to try diagnosing more specific problems. In my HQ-180AC, which I restored and then sold a few years ago, I don't remember seeing any paper or plastic ("bumblebee") capacitors. All of the small capacitors were ceramic or better, as I recall. Here is a photo of the chassis when I got the set. It's possible that someone had been there before me -- it has been a while. http://www.antiqueradio.org/art/hamm04.jpg In any case, I would not "shotgun" all of the small capacitors unless they are paper or plastic. Ceramics can fail, but they are generally much more reliable. This article may help you identify different capacitor types: http://antiqueradio.org/recap.htm . After you replace the electrolytics, you can try the set again, and if the problems persist, do more specific troubleshooting. Regards, Phil Nelson Phil's Old Radios http://antiqueradio.org/index.html |
HQ180A restore
Chuck Harris wrote:
I sure am glad you could clarify that. HQ-180A's don't have paper caps. Are you sure about that? I know the vast majority of caps in there are ceramic discs, but I recall some paper stuff as well in the detector stage. The ceramics do fail sometimes too, but not very often. It's a major pain to find them when they do, though. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
HQ180A restore
It has been a while since I was in one, but I am pretty sure.
There are some of those paper covered low voltage (3V?) electrolytics in the audio section, IIRC. -Chuck Scott Dorsey wrote: Chuck Harris wrote: I sure am glad you could clarify that. HQ-180A's don't have paper caps. Are you sure about that? I know the vast majority of caps in there are ceramic discs, but I recall some paper stuff as well in the detector stage. The ceramics do fail sometimes too, but not very often. It's a major pain to find them when they do, though. --scott |
HQ180A restore
I just checked the parts list for my HQ-180 (non-A model). It lists
3ea. 0.1uF, 200VDC and 3ea. 0.47uF, 400VDC "Dur-Paper" capacitors and a 0.033uF and 2ea. 0.01uF Mylar caps. All the rest of the small caps are ceramic and mica. Of course, the filters are electrolytics. --Ed |
HQ180A restore
Ed Engelken wrote:
I just checked the parts list for my HQ-180 (non-A model). It lists 3ea. 0.1uF, 200VDC and 3ea. 0.47uF, 400VDC "Dur-Paper" capacitors and a 0.033uF and 2ea. 0.01uF Mylar caps. All the rest of the small caps are ceramic and mica. Of course, the filters are electrolytics. --Ed Hmm? Maybe that is the difference between a plain and an "A" model? -Chuck |
HQ180A restore
On Feb 5, 3:11�pm, Chuck Harris wrote:
Ed Engelken wrote: I just checked the parts list for my HQ-180 (non-A model). �It lists 3ea. �0.1uF, 200VDC and 3ea. 0.47uF, 400VDC "Dur-Paper" capacitors and a 0.033uF and 2ea. 0.01uF Mylar caps. �All the rest of the small caps are ceramic and mica. �Of course, the filters are electrolytics. --Ed Hmm? �Maybe that is the difference between a plain and an "A" model? -Chuck wow, i never expected to gt so many replies..i sent off for a bunch of caps. that will be my first move. i figure after 40 yrs, the electrolytics need changing anyway. also the few paper caps. i will keep in touch after cap day. tnx agn, pete k2iqk |
HQ180A restore
Hmm? Maybe that is the difference between a plain and an "A" model?
The Osterman boatanchor book says this: "The newer A model features a solid state PS, 230VAC, 3 position BFO, accessory socket, less drift and 500 ohm line output." Phil Nelson |
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