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

Philco Jr.
#18

Sound like you've got the sensitivity up too high causing the detector to start oscillating. When it's oscillating it oscillate when it is turn across an am signal. This is what causes that tunable squeal that you are hearing. It's #18 the one with fiber nut on it. Back it out a turn or two and that should calm it down. This does not adjust the IF frequency but control the feedback in the detector circuit.
The fiber nut is easily broken never tighten it down it will crack. If the set is work right it doesn't need to be tight at all.

It is important to do the IF alignment for gain and selectivity. I noted two different fq 450kc & 460kc listed. I would probably pick 460kc that's a much more popular Philco fq, I can't think of any that use 450kc.

Once you get the IF peaked up then adjust the sensitivity just below the point of oscillation.

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


Messages In This Thread
Philco Jr. - by Jim Dutridge - 07-22-2024, 02:56 PM
RE: Philco Jr. - by Jim Dutridge - 07-22-2024, 06:00 PM
RE: Philco Jr. - by Ed Locker - 07-23-2024, 10:16 AM
RE: Philco Jr. - by Jim Dutridge - 07-23-2024, 11:51 AM
RE: Philco Jr. - by Jim Dutridge - 07-23-2024, 12:35 PM
RE: Philco Jr. - by Radioroslyn - 07-23-2024, 05:59 PM
RE: Philco Jr. - by Jim Dutridge - 07-23-2024, 07:33 PM
RE: Philco Jr. - by David - 07-23-2024, 08:35 PM
RE: Philco Jr. - by David - 07-23-2024, 08:40 PM
RE: Philco Jr. - by Radioroslyn - 07-23-2024, 09:44 PM
RE: Philco Jr. - by Jim Dutridge - 07-28-2024, 12:10 PM
RE: Philco Jr. - by Radioroslyn - 07-28-2024, 04:34 PM
RE: Philco Jr. - by Jim Dutridge - 07-29-2024, 08:55 AM
RE: Philco Jr. - by Radioroslyn - 07-29-2024, 04:14 PM
RE: Philco Jr. - by Jim Dutridge - 07-29-2024, 04:38 PM
RE: Philco Jr. - by Jim Dutridge - 07-31-2024, 04:21 PM
RE: Philco Jr. - by David - 07-31-2024, 07:59 PM
RE: Philco Jr. - by Radioroslyn - 07-31-2024, 10:00 PM
RE: Philco Jr. - by Jim Dutridge - 08-02-2024, 04:08 PM
RE: Philco Jr. - by Jim Dutridge - 08-09-2024, 02:53 PM
RE: Philco Jr. - by RodB - 08-09-2024, 08:39 PM



Users browsing this thread: 3 Guest(s)
[-]
Recent Posts
New Philco Repair Bench
I am sure this is the archive, and not the Chuck's site.morzh — 09:50 PM
Made mistake & did not label connection
It's not like we are good friends with that wire and can tell it from other ptetty identical looking wires. Why'n't you...morzh — 09:49 PM
Made mistake & did not label connection
I'm not sure why that wire wasn't covered in the video. I'm pretty sure the 6A8 won't work until that pin is grounded. Y...RodB — 09:47 PM
Made mistake & did not label connection
You'll have to forgive me, I am not sure what you mean.  Can you explain what you are really saying.  If anyone does not...georgetownjohn — 08:05 PM
Made mistake & did not label connection
Those are details better left to the ones who know. Maybe you disconnected the wrong end of the wire.RodB — 06:22 PM
Made mistake & did not label connection
Maybe this is starting to make some sense in my hard head.  Is this why the wire in question was not in the great Ron Ra...georgetownjohn — 04:34 PM
Made mistake & did not label connection
I was correct with the 6A8 pin connection's, 7 and 8 are connected to ground as well as the tube shield (the broken line...RodB — 02:41 PM
Made mistake & did not label connection
What does the dotted line representing that surrounds the tube in the schematic?georgetownjohn — 02:17 PM
Made mistake & did not label connection
Hello John, I have been there either label got lost or was not labeled ! Sincerely Richardradiorich — 02:15 PM
Made mistake & did not label connection
Sorry, it is a Philco 37-640.  Does that help?--Johngeorgetownjohn — 02:14 PM

[-]
Who's Online
There are currently no members online.

>