Posts: 1,114
Threads: 14
Joined: Feb 2013
City: Irvington, NY
Greg, the easiest way to check if the RF stage is oscillating is to take the 44 tube completely out. It cannot oscillate if the tube is not plugged in. Just removing the cap wire will not necessarily prevent the RF oscillation if that's what is happening. If you hear SW when the 44 tube is in, but not when its removed then most likely the RF stage is oscillating.
But that's not the main question. The real problem is why you don't hear broadcast stations when the antenna is connected to the 36 top cap and that can only be caused by the 36 and its osc circuit.
If you feed a 260 kHz IF signal into the grid cap of the 36 you should hear it well, but not into the 44 RF grid because the RF stage is not tuned to that freq and the signal will be attenuated.
Messages In This Thread
RE: Model 89 Cathedral - by Mondial - 03-10-2014, 08:34 PM
Users browsing this thread: 3 Guest(s)
|
Recent Posts
|
Need to purchase some accessories for restoration of my Old Philco Radio
|
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM |
First Radio restoration
|
Hi Tubeman,
Welcome to the Philco Phorum. Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM |
First Radio restoration
|
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM |
Zenith H725
|
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately.
More ...EdHolland — 10:18 AM |
Graphics for majestic 1050 dial glass.
|
Murf;
I found this thread on the ARF, the first photo has a pretty good view of the dial glass.
Regards
ArranArran — 01:12 AM |
Zenith H725
|
hello Ed,
how about that speacial tape used for ducting it's like foil or how about thin piece of
aluminum roof flash...radiorich — 12:19 AM |
Zenith H725
|
Ed;
One material that I have seen, but never tried for this was material for making exhaust gaskets, it's similar to ...Arran — 11:42 PM |
Zenith H725
|
I just remembered, I have some hi temp silicone rubber material which could do the trick. Or a piece of FR4 laminate. Th...EdHolland — 08:39 PM |
Zenith H725
|
The PSU filter cap arrived today (thank you USPS!) so I will work on that later.
Meanwhile, I have the dial, speaker...EdHolland — 06:42 PM |
Philco 610B oscillator wiring
|
Thanks Terry. After checking my notes I think I recorded about -10v at the 6A7 G4/control grid. The screen grid (G3 &...Tubester — 05:59 PM |
Who's Online
|
There are currently 1614 online users. [Complete List] » 1 Member(s) | 1613 Guest(s)
|
|
|

|