Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

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

FStephenMasek's Philco 112 chassis restoration
#5

Any ideas ? It is playing up and down the dial, but with low volume. Please consider the following facts:
1) the voltages at the tube sockets all look good, perhaps a bit high (e.g. 187 on the plate of the 1st RF tube, 275 on the plates of the '47 tubes);
2) Both '47 tubes are good and test the same
3) All of the other tubes have been tested and are at or above the reading showing on the roll chart of my Hickok
4) The plate voltage at the 1st Audio Tube is just 89. Bypassing Resistor Number 46 increases it to 138V, but with no increase in volume.
5) Jumping the volume control makes no difference from setting the volume control at maximum
6) All fixed capacitors, except a few mica units which test properly, were replaced
7) The audio inter-stage transformer primary measures something in the 4.5K range, and the secondary something like 5.5K ohms.

It took me too long to finally determine that one of the capacitors numbered 25 on the schematic was missing. It only worked at the low end of the dial, and RF alignment was impossible. Both number 25 were originally metal cans, long gone from this chassis.

By the way, the schematic notes that there are two capacitors numbered 34, but that is incorrect.

Web site: http://www.masekconsulting.net
Radio Photos: http://www.photobucket.com - album id FStephenMasek


Messages In This Thread
RE: FStephenMasek's Philco 112 chassis restoration - by FStephenMasek - 06-11-2017, 08:09 PM



Users browsing this thread:
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
Well, maybe - maybe not  :lol: It's been an interesting project so far! Something so simple, yet so cranky. The 1st one ...TV MAN — 05:12 PM
1949 Motorola 5A9M
Haven't thought of Burgess batteres in a while  https://www.radionostalgia.ca/lib/Images/battery/us/burgess1D.jpgi ...Vlad95 — 03:50 PM
Philco Model 16 wiring question
Measure the voltages first, just in case.morzh — 02:19 PM
1949 Motorola 5A9M
Haven't thought of Burgess batteries in a while Mr. Fixer. Boston Edison always used Burgess in their Bright Star yellow...Paul Philco322 — 02:17 PM
1949 Motorola 5A9M
Thanks Sam. I'll let you know. I can probably scare some up from the local radio club.klondike98 — 02:07 PM
Philco 89 Code 123 Osc Coil
Hello,  I thought I would post my findings on my bad oscillator tickler coil. There were 27 turns on the outer coil b...dconant — 12:38 PM
Philco Model 16 wiring question
Thanks Morzh. So it appears I did wire it incorrectly and I have to switch the wires between pins 2 and 4.bobclausen — 09:24 AM
Philco 46-1209 strange behavior
No, it's not a problem, just during certain condition it could show up. Yes, an internal tube short could do that too. ...morzh — 09:13 AM
HiFi (Chifi) tube amp build - but my own design.
You sound guys are never satisfied. :crazy: :clap:RodB — 09:10 AM
HiFi (Chifi) tube amp build - but my own design.
I got some new ceramic octal tube sockets installed and also tried some different coupling caps.  The results:  The go...TV MAN — 08:42 AM

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

>