Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Antique Radio

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #31  
Old 01-19-2018, 12:07 PM
Winky Dink's Avatar
Winky Dink Winky Dink is offline
VideoKarma Member
 
Join Date: Apr 2010
Location: Meridian, Idaho.
Posts: 583
Yes. It was easy to replace the grommets.

Turning to electronics,

Previous suggestion:
"I would break the connection between the plate of the 57 and the 1 meg pot and insert a capacitor there, to take the pot out of the DC path. Likely a .05 would be ok in that location...I would also try a larger value for C-9 for a more mellow tone...”

My reply:
Replacing C9 with .01uF did improve the tone, and replacing R9 with 100Kohms restored the original plate voltage. I also tried putting a cap between the plate and the volume pot, but that seemed to have no effect except to lower the sound level. At this point, the audio is satisfactory.

A subsequent suggestion:
"The way you had the volume pot connected was semi-correct. You need to use a cap .02 to .05mfd between the plate of the 1st amp tube and the high end of the volume control. The wiper would go to C7 and the low end to ground, as you had it. It should correct your distortion problem."

Is this the same as the previous suggestion? The blue is how I wired it before, but noted no improvement and removed the capacitor. So I humbly ask if there is something "semi-INCORRECT" in this picture?"

__________________
Winky Dink
Damn the patina,
Full speed ahead!
Reply With Quote
  #32  
Old 01-23-2018, 11:40 PM
Winky Dink's Avatar
Winky Dink Winky Dink is offline
VideoKarma Member
 
Join Date: Apr 2010
Location: Meridian, Idaho.
Posts: 583
Finished.

The final configuration is diagrammed above. I don't remember specifically what I used for C-15, but I'm not gonna pull the chassis again to find out. This is what I ended up with after a lot of experimenting. Here's a link to a 13-second audio sample:

https://flic.kr/p/23F6oQ6

I think that's fairly good for a budget radio with a 4-inch speaker.

Thanks again. It's a nice-looking set and it'll be great for listening to the ball game, but maybe not so good for Toscanini. More importantly, it makes me happy.
__________________
Winky Dink
Damn the patina,
Full speed ahead!
Reply With Quote
  #33  
Old 01-24-2018, 10:53 AM
dieseljeep dieseljeep is offline
VideoKarma Member
 
Join Date: Jul 2010
Posts: 7,562
Quote:
Originally Posted by Winky Dink View Post
The final configuration is diagrammed above. I don't remember specifically what I used for C-15, but I'm not gonna pull the chassis again to find out. This is what I ended up with after a lot of experimenting. Here's a link to a 13-second audio sample:

https://flic.kr/p/23F6oQ6

I think that's fairly good for a budget radio with a 4-inch speaker.

Thanks again. It's a nice-looking set and it'll be great for listening to the ball game, but maybe not so good for Toscanini. More importantly, it makes me happy.
That's the way I would've done it!
How does it sound with the gain control "maxed out"? The improvements you incorporated is still a great way to increase the enjoyment of this set, even though it's no longer "pure".
Reply With Quote
  #34  
Old 01-24-2018, 12:12 PM
Winky Dink's Avatar
Winky Dink Winky Dink is offline
VideoKarma Member
 
Join Date: Apr 2010
Location: Meridian, Idaho.
Posts: 583
It works just as explained to me here. Max gain is too much the stronger stations, in which case lowering the gain will reduce the distortion. In fact, the audio is the sample is not the best--it probably could have been improved a bit by tweaking the gain. It is a more enjoyable toy with the extra gimmicks to play with.
__________________
Winky Dink
Damn the patina,
Full speed ahead!
Reply With Quote
  #35  
Old 01-24-2018, 01:04 PM
jr_tech's Avatar
jr_tech jr_tech is offline
VideoKarma Member
 
Join Date: Sep 2009
Posts: 4,510


When you crank up the "RF Gain" control at night can you receive many of the western US powerhouse stations such as KSL, KEX, KOA?... in other words, is it a fairly decent DX set, since it has a RF stage?

jr
Reply With Quote
Audiokarma
  #36  
Old 01-24-2018, 08:08 PM
old_coot88 old_coot88 is offline
VideoKarma Member
 
Join Date: Sep 2009
Posts: 2,541
Wonder if the two IF trimmers are fully 'on peak'. Unless peaked on a weak signal, a tiny fraction of a turn can make a big difference DXing.
Reply With Quote
  #37  
Old 01-24-2018, 11:50 PM
Winky Dink's Avatar
Winky Dink Winky Dink is offline
VideoKarma Member
 
Join Date: Apr 2010
Location: Meridian, Idaho.
Posts: 583
At this time, it's not a decent DX set. I found KOA, and it was not easy listening. Not having the patience to wait for a station ID, I found KOA online to confirm what I was listening to. However, as old coot88 points out, I haven't redone the alignment since I got the set working properly. That sounds like a worthwhile endeavor. Maybe I could work on that Friday morning. What... I have a dental appointment Friday? I'll just have to cancel that.
__________________
Winky Dink
Damn the patina,
Full speed ahead!
Reply With Quote
  #38  
Old 01-25-2018, 09:29 AM
old_coot88 old_coot88 is offline
VideoKarma Member
 
Join Date: Sep 2009
Posts: 2,541
With just two (not 4) IF trimmers, it shouldn't need more than a a tweak to be sure they're 'on the peak'. But peak it on the weakest signal that you can tune in.
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 08:41 AM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.