EH Scott Radio Enthusiasts

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Philharmonic Receiver, Photos of components near chassis plug?

There appears to have been some major quick repairs to the underside of my Philharmonic receiver in the area where the chassis plug exits. If anyone has any photographs of how this area should appear, I would appreciate looking at them. They will help me figure out what goes where.

There is what looks like a multiple-section resistor on the end wall (marked '523', possibly the B voltage divider). Some of the leads coming from this go to large solder blobs where 3-4 wires are joined and just hanging in the air. Also it appears that a red lead was attached at one point and it went to a 2000 ohm ceramic resistor (now broken off) that was attached to nothing on the other end.

So, any archived photos  someone might have may be helpful. I have included a couple of my own to show the area in question. Thanks.

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Ken:

This is a problem that is difficult to address through photos because the other ends of many of those wires are not near the divider resistor and the colors have faded.  Without another chassis handy for reference, the best approach to address what appears to be a problem with the circuit is to compare to the circuit diagram.  This is a daunting task for anyone who is not intimately familiar with circuit diagrams and chassis wiring practices.  Short of that task, try to set up a meeting with a member of this forum having experience working on the Philharmonic to assist with verification or correction of the circuit.  If you were near the California-Oregon border I would gladly help!

Norman

Norman... love your answer...thanks for the advice. I believe seeing another Phil would help greatly. I was actually near Oregon recently when we were in Seatle (took an Alaskan cruise).
I will check for someone nearby. I also plan to study and trace that diagram carefully. Like you said, they are difficult to follow since they often do not resemble the actual physical layout.

Can you confirm that the item that looks like a multi- section resistor is the B voltage divider?
Thanks again!

Hi  second and 3rd photos look to be the B divider! Best to have someone work with you whos fixed a Philly 30 befor, many wires that go everywhere! Tuning condenser you have to either cut all wires going to it or unsolder the grid caps from each wire.Then you can take the cover off.You fine that cover is heavy mines lined with lead! Good luck with itAngelo

Angelo,
Thanks on ID of voltage divider. I will keep an eye out for a local expert as you and Norman suggest.

I will desolder those leads then. At least that is not destructive.

Is the tuning dial just direct drive through those pulleys or is there supposed to be a string and spring arrangement?
Thanks so much.


Angelo said:

Hi  second and 3rd photos look to be the B divider! Best to have someone work with you whos fixed a Philly 30 befor, many wires that go everywhere! Tuning condenser you have to either cut all wires going to it or unsolder the grid caps from each wire.Then you can take the cover off.You fine that cover is heavy mines lined with lead! Good luck with itAngelo

Ken,

Regarding the grid wires exiting the tuning cap cover, IF cans, etc. Here is my approach.

-The original wires often have compromised insulation after all these years. So figure on replacement. Scavenge the original grid cap for reuse. Try to match the color appearance of the new wire to the old, be it cloth covered or rubber covered. Use multi strand wire. Test lead wire is a good replacement for rubber covered wire.
- Take care of whatever else is inside the cover or can. On the Philharmonic and other models, look for the foil/paper/wax caps positioned half inside coming up from below, and replace the cap. Even If an occasional cap looks like it has been replaced before, assume it too is failing and replace it also. Use modern caps - film,polyester. - not old or new old stock. Check continuity of anything inside the cover or can to avoid an "OOPS! moment" later.
- Size the new grid cap wire maybe twice as long as the old or more. After soldering the new wire in place, feed the other end hrough from the inside. For multiple wires coming out of the tuning cap cover, temporarily wrap each wire end with tape to avoid accidently losing it inside while remounting the cover.
-When the cover is successfully mounted, then cut each grid wire to length and solder the on the grid cap. Allow enough extra length that you (or some future owner) could use the shorter metal or GT size tubes.
- INOTE I have tried soldering fine wire to original grid cap wire lengths, for purposes of threading through the cover, but don't recommend doing so. I just start with generous lengths and save the cut off's for other uses.
- NOTE: Scott suppled glass G tubes (6K7-G, 6J5-G etc), with some exceptions on the 1940-1 for the FM/AM sets. The metal and GT tubes have a larger diameter base too big to fit tube shield bases on some Scott models. Hence, gather some spare G tubes when you can.

David - great suggestions! I may even have some suitable cloth-covered wire in my junk box. I save everything.
I did notice those capacitors that look like groundhogs in their holes. At first I had no idea what they were. Who would hide half of a capacitor? Then I realized they emerge on the other side in various cans, etc. The wires coming out of the tuning cap were a real surprise. I could not believe an engineer would allow such design. I thought I had to be missing something. Of course today who can even find all the spark plugs on their car, never mind remove them.

I am seeing mostly G tubes. I have yet to test them all. I now am able to power up the receiver such that all tubes, including the purple gas voltage regulator and the two eye tubes glow. Very little hiss from speaker. I shut down because I need to make repairs to the area near the voltage divider. I think it has a chance so long as I am cautious and learn as I go along.
You and others have been very helpful. Thanks.

Ken by the audio section on the RX you find a square chrome cover ,remove it has a bunch of paper caps in it! Its on back left hand side of receiver if. Many miss that! Replace all caps in the AGC section and check all resistors in it to.You will be glad you did.Check the 1 meg resistor for the tuning eye tube they often change in value, its in the base of the socket. I replaced all my leads from the cans and tuning section to grid caps with Teflon coated wire I had on hand.Another thing use alcohol to clean band switch.Flood it good while changing bands.Scott used RCA  G tubes I found them to last long time.6L6s if you play the set a lot as I have I found either RCA OR SLYVAINA 6L6gs last the longest.Ihave owned my Philly 30 since 1978 !Chrome wax will help clean it and keep it shiney to.Good luck !

Angelo,
Thanks for all the tips! Almost all the tubes presently in the set are Sylvania.
I am amazed you have been running the set since 1978. That says a lot for Scott and your maintenance.
I will be back working on the set soon .. my wife and I just went to Maine fo a few days. Unfortunately I did not buy any new radios (LOL).

Sylvania tubes were original equipment in many Scott receivers including at least the early Philharmonic receivers.  The rectangular can above the chassis containing, as i recall, four wax-paper capacitors is part of the record scratch suppressor circuit.  I have not checked but it is possible that these capacitors are out of the circuit unless the record scratch suppressor is activated.  Scott did not design the circuits to run the tubes hard therefore tubes of all good brands should last a long time.

Norman

Norman,
Interesting that you mention the scratch supressor. The pot and shaft for mine are missing. Someone removed it and taped off the two leads. Any chance you know the values for that control? I have a lot of spares and various shaft lengths.

Ken -- The Scratch Suppressor control is just a toggle switch (on-off) and not a pot. On my pointer Philly, it is a push-pull switch, with a shaft long enough to protrude about 1/2 inch through the wood control panel below the tuning knobs.. For later models with 8 control knobs, it is one of the additional controls, again with a long shaft. I suppose it could be push-pull or right-left which ever you can locate with a sufficiently long shaft.

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