Home |
Search |
Today's Posts |
#1
![]() |
|||
|
|||
![]()
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 |
#2
![]() |
|||
|
|||
![]() wrote in message ... 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 Oscillation and tunable hum can be caused by bad decoupling and by-pass capacitors. If you don't have a handbook try BAMA for one. You may have to shotgun the caps. -- --- Richard Knoppow Los Angeles, CA, USA |
#3
![]() |
|||
|
|||
![]()
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 |
#4
![]() |
|||
|
|||
![]() 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 |
#5
![]() |
|||
|
|||
![]() 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 |
#6
![]() |
|||
|
|||
![]()
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 |
#7
![]() |
|||
|
|||
![]()
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." |
#8
![]() |
|||
|
|||
![]() "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." |
#9
![]() |
|||
|
|||
![]()
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 |
#10
![]() |
|||
|
|||
![]()
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. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Lastest restore | Radio Photos | |||
Fada 43Z cabinet restore | Radio Photos | |||
WTB: R-390 / R-390A (Restore?) | Swap | |||
HQ180A Record Price? | Shortwave | |||
how do you restore a bc80xlt? | Scanner |