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

37-9 poor reception at low frequencies
#1

All electrolytic, tubular, and Bakelite caps are new. Also new tuner support bushings. There is some reception at the higher end of the AM band, none below about 700Khz, and none that I can tell on SW bands.Cathode resistors on 6A8 and 6N7 check ok. R2 OK.
I am able to force a signal from my generator, perhaps it just needs a better antenna than i'm providing. Open for suggestions at this point.
Thanks
Cornell
#2

I would do the alignment. You maybe able to tell whats not aligning properly. Also check plate and screen grid voltage on the RF and mixer. Clean band switch. Do you see any black coils? Lightning Bad mica cap will cause this issue. I'm assuming that the tube test GOOD
GL
Terry
#3

Agreewith all, but also check to see if tuning cap shorts at or below 700K. Usually one of the outside rotors is bent or there is some dirt . You should be able to slide a piece of paper between rotor and stator and locate where it "catches", or use ohmmeter. This happens frequently on the lower side, as the fins are nearly entirely meshed.




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
12' Philco
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM
Hickok AC51 tube tester
I think they have only shown the secondaries of the transformer. Two of them feed the rectifiers' filaments.morzh — 12:58 PM
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM
Hickok AC51 tube tester
Absolutely no one is going to reverse engineer that circuit. Even the iron core is missing.RodB — 10:37 AM
IF can wire size and Rubber mounts?
Thanks to both members for your help regarding wire and tuner mtg supports. regards--Johngeorgetownjohn — 09:33 AM
Hickok AC51 tube tester
Note that no power cord, power switch, or power transformer switch are shown. That (along with my experience with full s...DaleHCook — 07:09 AM
IF can wire size and Rubber mounts?
A pair of wire strippers can give you an idea of what the existing gauge of the wire leads are in the IF can, I think it...Arran — 06:07 AM
My last cabinet for this year
Hello Dan, That is really beautiful what great looking radio you have ! I have friends who live in Calgary and the wea...radiorich — 01:51 AM
Philco Predicta Siesta picture over time getting dimmer
I found that the wire insulation was burnt.  The fly back needs corona dope! Why would someone put that there?Platinumblonde36 — 01:09 AM

[-]
Who's Online
There are currently 5039 online users. [Complete List]
» 1 Member(s) | 5038 Guest(s)
Avatar

>