1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Linear Mode
Philco Model 87
Chas
Senior Member
****
Posts: 696
Threads: 8
Joined: Apr 2018
City: S. Dartmouth State, Province, Country: MA
#10

08-30-2023, 11:43 PM
The NULL is the correct response when neutralizing a common TRF. If the adjustment is not working something is wrong in the circuit(s). The correct tuner frequency to neutralize may not be the one specified. So if the set still oscillates at a certain receive frequency, neutralize at that frequency. All shields must be in place, if a bottom plate is used be sure it is on too. Do not work on a metal bench raise the radio a couple of inches if a metal bench is in use and there is no bottom plate required. it is best to keep the tubes in their respective positions once the set is neutralized.


Be sure the filament voltage is correct at all the 26 tubes, poor connections are a problem for those high filament amp tubes.

GL

Chas
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
Find
« Next Oldest | Next Newest »


Messages In This Thread
Philco Model 87 - by fwmartin2000 - 08-29-2023, 08:28 PM
RE: Philco Model 87 - by MrFixr55 - 08-29-2023, 09:07 PM
RE: Philco Model 87 - by Radioroslyn - 08-29-2023, 09:17 PM
RE: Philco Model 87 - by morzh - 08-29-2023, 10:35 PM
RE: Philco Model 87 - by radiorich - 08-30-2023, 12:15 AM
RE: Philco Model 87 - by fwmartin2000 - 08-30-2023, 11:53 AM
RE: Philco Model 87 - by Radioroslyn - 08-30-2023, 12:19 PM
RE: Philco Model 87 - by morzh - 08-30-2023, 07:16 PM
RE: Philco Model 87 - by fwmartin2000 - 08-30-2023, 09:22 PM
RE: Philco Model 87 - by Chas - 08-30-2023, 11:43 PM
RE: Philco Model 87 - by morzh - 08-31-2023, 10:08 AM
RE: Philco Model 87 - by fwmartin2000 - 09-06-2023, 03:16 PM
RE: Philco Model 87 - by Chas - 09-06-2023, 05:17 PM
RE: Philco Model 87 - by fwmartin2000 - 09-07-2023, 08:51 PM



Users browsing this thread: 1 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.

>
  1. The PHILCO Phorum
  2. Philco Radio Discussions
  3. Philco Electronic Restoration