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

48-1262 no sound
#1

In a previous post, I complained of low voltage. I replaced the 50 x 6, and the voltages came up just fine, though a little high. I also replaced one resistor that was open. All I hear now from the speaker is a dull hum.

I performed the oscillator test with guidance from the manual, and the voltage readings are .02 instead of the required -3.3 to 4.2 (if I did it correctly); ohms at the coil read 3.0. Voltages on the 14AF7 are good at the test points.

The trouble shooting guide Section 4 says for the osciallator test says to "connect the negative lead of the voltmeter through a 100K ohm resistor to osciallator grid, test point D."

My question is where does the 100K ohm resistor attach? As I read the instructions, it looks like I attach it to an alligator clip lead in line. Is that correct?

If this checks out ok, I will move to the audio transformer, but as Scarlett O'hara said, "tomorrow is another day."

Thanks for all your help in advance.

Terry
#2

Positive lead of the meter to the negative side of the filter capacitors. The 100K resistor connects between your negative lead and pin 4 of the 14AF7.
#3

Thanks Jim. I think I did this correctly last night, but I will check again on Monday. If my voltages are low, is there another check I can do to see why they are low and what parts may be bad?




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
New Philco Repair Bench
Morzh is correct. The repair bench on our website is an archived image of chuck’s original site. He no longer provides s...klondike98 — 05:32 PM
Made mistake & did not label connection
Excellent information. It is all starting to come together now and your explanation really helped since I noticed that ...georgetownjohn — 04:39 PM
Made mistake & did not label connection
Hi John, I don't have this radio, but I can supply some info: Based on your pic, pins 7,8 and 1 are used together, go...MrFixr55 — 02:02 PM
New Philco Repair Bench
As far as I know, the Repairbench does not work, and has not been working in a while. Chuck (we had that campaign looki...morzh — 01:33 PM
Radio city products 664 schematic request
Need a schematic or manual for the 664. The 663 may be similar.daveone23 — 12:38 PM
New Philco Repair Bench
Thanks Gary.dconant — 12:16 PM
New Philco Repair Bench
I tried accessing the site through our library and got the same response. It's reported to our tech gurus. GaryGarySP — 11:50 AM
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

[-]
Who's Online
There are currently 3936 online users. [Complete List]
» 3 Member(s) | 3933 Guest(s)
AvatarAvatarAvatar

>