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

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

Cannot Adjust an IF Transformer’s cores
#42

I mistyped the last sentence from the first paragraph of my last post. I meant to write, "I may encounter different results if I don’t proactively address the issue now."

    In any event, I have worked on a redesign in order for the two trimmer caps to be accessible while the can is in place. I have designed two PCBs, an upper and a lower. The lower board will comprise the majority of the system. It has connections 1, 2, 3, and 4 (one in each corner) for the four incoming/outgoing connections to the rest of the radio. It also has a space for the primary trimmer cap (to be mounted on the underside for access from the bottom of the chassis), the primary fixed capacitor, and both inductors. I have confirmed from experimentation that these two radial lead inductors need to stay side by side for best results. There are also four through-hole cut-outs for jumpers to the upper PCB. For both structural and electrical connection, I plan to use these vertical header pins which are used for connecting two stacked PCBs. I will only need two sets of single-row, double-pin connectors.
   

    Here are top and bottom views of the lower PCB.
   
   


    The upper PCB will consist of the secondary fixed capacitor and trimmer cap (centered and facing up for access from the top of the can). It features the same four through-hole cut-outs for soldering to the vertical header pins. Here are top and bottom views of the upper PCB.
   
   

    For clarity, I have attached the two schematics for the upper and lower board.


Attached Files
.pdf Lower PCB.pdf Size: 15.81 KB  Downloads: 106
.pdf Upper PCB.pdf Size: 11.81 KB  Downloads: 103

Joseph

Philco 46-480
Philco 49-906


Messages In This Thread
462ron - by 462ron - 08-01-2024, 07:33 AM
462ron - by 462ron - 08-01-2024, 08:44 AM
462ron - by 462ron - 08-02-2024, 08:09 AM
462ron - by 462ron - 08-03-2024, 07:49 AM
462ron - by 462ron - 08-04-2024, 08:15 AM
462ron - by 462ron - 08-08-2024, 08:02 AM
462ron - by 462ron - 08-10-2024, 08:33 AM
462ron - by 462ron - 08-10-2024, 09:38 AM
RE: Cannot Adjust an IF Transformer’s cores - by jrblasde - 08-10-2024, 07:23 PM
462ron - by 462ron - 08-12-2024, 07:42 AM
462ron - by 462ron - 08-25-2024, 08:27 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 42-345 Restoration/Repair
RodB :beerchug:Vlad95 — 10:22 AM
Philco 42-345 Restoration/Repair
Vlad, you nailed it. Swiss and German roots.RodB — 09:54 AM
5U4 vs 5Z4 tubes
Well this is a Hallicrafters SX/9 circa 1936. No real issues so far although I dodged a real bullet with a cap that was...bridkarl — 07:59 AM
5U4 vs 5Z4 tubes
The pinout is the same but the 5U4 has a 3 amp filament, verses 2 amps or less on the 5Z4. I think that the pinout of a ...Arran — 12:04 AM
Philco 42-345 Restoration/Repair
By the way. osanders0311 Take a look here: Dial cord stringing Guides May be here you can fount correct string settin...Vlad95 — 11:15 PM
5U4 vs 5Z4 tubes
5U4 and 5Z4 almost identical. I think nothing happened if you left 5U4 instedad 5Z4 long time. Just heater current 5U4 ...Vlad95 — 11:02 PM
Philco 42-345 Restoration/Repair
Hello Vlad95 , Very Funny ! Sincerely Richardradiorich — 11:01 PM
Philco 42-345 Restoration/Repair
RodB You are European yourself   :evil: I'm Canadian for the last 30 years  :snowman: But not Yankee  :lol: Vlad95 — 10:49 PM
Philco 42-345 Restoration/Repair
The band switch selects different oscillator coils for the band selected. I would look for a bad connection in the switc...RodB — 10:31 PM
Philco 42-345 Restoration/Repair
Hang in there...PaulPaul Philco322 — 09:30 PM

[-]
Who's Online
There are currently 1034 online users. [Complete List]
» 1 Member(s) | 1033 Guest(s)
Avatar

>