Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Noisy Silvertone
#1

I've just finished restoring a Silvertone Model 1908. Reception is good BUT off-station the radio is very noisy (squeals). Once a station is tuned-in, the radio is reasonably quiet. However, tuning is difficult; that is, very narrow "quiet" range requiring very precise, delicate tuning to quiet radio. The squeals seem worse at the high end of the AM band.

Any suggestions would be welcome.

Thanks,

Don
#2

Sound like your IF amp is oscillating. Try touching the grid cap on the 6K7 and to hear if it clears up. May drop the gain a bit. If so realign the IF transformers if it still persists detune one of the IF trimmers.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

Thanks, I'll try that.

Don
#4

Actually, this sounds like the exact issue my RCA 19K developed. Sounds like it needs the same thing done to it for the problem.

No matter where you go, there you are.
#5

I'm sorry, I am not familiar with what you did for your RCA. Could you elaborate?

Thank you,

Don
#6

I haven't done anything for the problem yet. I was just mentioning that my RCA seems to have the same problem, really noisy between stations and hard to get tuned in just like your Silvertone. So, I am hoping the solution mentioned will work for both of us. Icon_smile

No matter where you go, there you are.
#7

OK, thanks. Here's hoping.
#8

There may also be an issue with the AVC bypass capacitor, it could be open circuit or missing. Another thing to look at are grid caps and grid cap leads, sometimes the solder joints on the grid caps get flaky, as does the solder joint on the clip that goes on it, the wire can also break internally. Another source of oscillation can be the first audio tube, if it is a glass type like a 6Q7G or a 75 they cause a squeal with the shield removed.
Regards
Arran
#9

Thanks, Arran. I'll get into troubleshooting tomorrow. I'll post what I find.

Don
#10

The AVC bypass cap was in-circuit and correct value per the schematic. However, increasing the bypass cap value quieted the radio substantially. Tuning is now much easier and the audio is cleaner once tuned. The radio now performs as I expect it to.

Thanks for the tips,

Don




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Philco 91 Speaker Replacement
The spider is glued on the cone and so is the voice coil. I think you can use a cotton swab dipped in acetone and carefu...RodB — 02:42 PM
Restoring Philco 37-604C
Yes I saw that. If I knew, I'd probably try to arrange for getting it myself. But I have just got one. Which does not m...morzh — 01:44 PM
Philco 38-2 Automatic Tuning
When you push the lever, you are supposed to rotate the disk to the desired station. Then the magnetic tuning will acqu...morzh — 01:42 PM
Philco 38-2 Automatic Tuning
I figure out the muting from another picture that helped. Now I need to know how the automatic tuning works. When I push...dconant — 12:11 PM
Philco 91 Speaker Replacement
How would I go about removing the spider from the cone?dconant — 12:04 PM
Philco 38-2 Automatic Tuning
Hello, I am having trouble getting my automatic tuning to stay unmuted. If I play with the tuning handle I can get it to...dconant — 10:51 AM
Does anyone make photofinish replacements?
Here’s the link to the DIY photofinish section of our site: klondike98 — 09:46 AM
Delco car radio Peko vibrator converstion issues
Hi Richard, Thx for posting the schematic.  As I remember as a kid, these were great performers for the time, likely...MrFixr55 — 08:56 AM
Delco car radio Peko vibrator converstion issues
hello mr Fixr, The Electro  Powersupply that I am powering the radio with has a huge choke plus a 10,000ufd electrolyti...radiorich — 10:58 PM
Delco car radio Peko vibrator converstion issues
How about putting a choke in the power supply? The big cap was likely an attempt to stabilize the DC. Kids who cre...MrFixr55 — 09:19 PM

[-]
Who's Online
There are currently 3050 online users. [Complete List]
» 1 Member(s) | 3049 Guest(s)
Avatar

>