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

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

Linear Mode
reduce voltage
rghines1
Member
***
Posts: 190
Threads: 8
Joined: Oct 2005
City: Lexington, SC
#12

03-18-2010, 06:37 PM
Another thing to check is the negative bias going to the 45 tubes. If any of those resistors labeled 57 and 58 are open or increased dramatically it will also cause a large increase of voltage across the caps in the power supply. Resistor 59 in the cathode circuit of the 45 tubes is worth checking too. It could cause higher than normal B+. These resistors balance the loading of the power supply and should be within 20% tolerance.
Find
« Next Oldest | Next Newest »
Thread Closed


Messages In This Thread
reduce voltage - by denver - 03-17-2010, 02:12 PM
Re: reduce voltage - by rghines1 - 03-17-2010, 05:41 PM
Re: reduce voltage - by denver - 03-17-2010, 05:50 PM
Re: reduce voltage - by denver - 03-17-2010, 05:54 PM
Re: reduce voltage - by rghines1 - 03-17-2010, 08:09 PM
Re: reduce voltage - by denver - 03-17-2010, 08:22 PM
Re: reduce voltage - by Ron Ramirez - 03-17-2010, 08:37 PM
Re: reduce voltage - by denver - 03-17-2010, 09:39 PM
Re: reduce voltage - by Carl Travis - 03-17-2010, 09:44 PM
Re: reduce voltage - by rghines1 - 03-18-2010, 08:13 AM
Re: reduce voltage - by denver - 03-18-2010, 01:58 PM
Re: reduce voltage - by rghines1 - 03-18-2010, 06:37 PM
Re: reduce voltage - by denver - 03-18-2010, 07:37 PM
Re: reduce voltage - by denver - 03-21-2010, 07:04 PM
Re: reduce voltage - by denver - 04-06-2010, 04:22 PM
Re: reduce voltage - by Ron Ramirez - 04-06-2010, 05:05 PM
Re: reduce voltage - by rghines1 - 04-07-2010, 09:28 AM
Re: reduce voltage - by codefox1 - 04-07-2010, 11:27 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
An attempt to remove the Field Coil from a G speaker
Gary I in fact did, on a 38-14, I think, where I had a speaker with the dead coil. Well...it kinda worked. Kinda, be...morzh — 10:38 PM
An attempt to remove the Field Coil from a G speaker
Mike, what ever happened to that plan you had to try using a rare earth magnet to magnetize the pole? This looks like a...GarySP — 10:25 PM
RCA T62 is playing.....
Beautiful set.morzh — 09:07 PM
An attempt to remove the Field Coil from a G speaker
Well....here it is. The green stuff. Unfortunately, probably penetrates deep. I opened the top layer and saw that: ...morzh — 08:58 PM
Philco 91 Restore Code ??
:clap: :clap: :clap: :clap: Really nice workmanship!!! Top of the chassis looks great. Sorry about the long winded e...MrFixr55 — 08:09 PM
Philco 40-120C Restoration
Thank you for your reply. I will check voltages on the other tubes, look at resistor 23 and cap 25, etc. If all else fai...bluecap — 07:58 PM
RCA T62 is playing.....
Nice looking set great save. DavidDavid — 07:48 PM
Philco 89 indicator light.
Hello Jim, I have done several 89s. The trick is to move the drum in or out on it's shaft. You will need to loosen a set...dconant — 07:36 PM
An attempt to remove the Field Coil from a G speaker
MrFixr Yes, it is my plan to go with 45rpm spider if I go that far. No, the pole was not left-handed as I unscrewed ...morzh — 07:14 PM
Philco 40-120C Restoration
Change the tube. Check the tube's bias network. Are any other tubes experience the drop or just this?` Is resistor 23 OK...morzh — 07:09 PM

[-]
Who's Online
There are currently no members online.

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