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

Power supply design needed from master designer Terry
#11

Terry,

What are we shooting for on the B + with the two voltage divider resistors? Is it still 90v for this set? I'm seeing 135v on the two plates for the 1J6 output tube on the schematic which leads me to believe it may require more than 90.

Last time we were looking at two resistors adding up to 10K to make up the voltage divider.

Last time I found if I used a 4K from the + side of the 47 mfd to B +, and a 5K between the B + & B -, I got 94 volts. But that was without a load. Once I tried it on the radio, it dropped down to 76 volts, so apparently I need a higher value resistor than 5K between the B + & B -, and a smaller value resistor than 4K from the + of the 47 mfd to B + in order to get 100v without a load.

Greg V.
West Bend, WI
Member WARCI.org


Messages In This Thread
RE: Power supply design needed from master designer Terry - by NostalgiaRadioTime - 01-04-2022, 12:16 AM



Users browsing this thread:
[-]
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 1008 online users. [Complete List]
» 1 Member(s) | 1007 Guest(s)
Avatar

>