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

My introduction
#3

A fully tube functional radio will pretty much discharge most of the charge because current continues to flow after the set is off. Not so when there is no load. A capacitor is capable of storing a charge for hours, if not days. I use a 10K 2 watt resistor and test leads to discharge anything I'm working on. Leave this attached for at least 10 seconds to drain all the juice out.

And I usually install a "bleeder" resistor of about 100-or 200 K across the main resovoir as a further safety measure when I rebuild something. Two resistors in series, if the voltage is over 400 volts.

You should replace all the electrolytics and paper capacitors in the set before you apply any voltage to it. The cost is very little compared with the likelyhood of burning up an expensive tube or transformer. If you have to replace the wiring as well, I would probably go ahead and replace all the carbon resistors as well (you will find that in most cases they have increased in ohmage,) and this can make a big difference in performance once you are finally done with the set.

Good Luck


Messages In This Thread
My introduction - by Guest - 04-13-2010, 12:06 PM
Re: My introduction - by Uffda - 04-13-2010, 03:30 PM
Re: My introduction - by codefox1 - 04-13-2010, 03:58 PM
Re: My introduction - by Ron Ramirez - 04-27-2010, 07:56 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco Model 16 wiring question
Thanks Morzh. So it appears I did wire it incorrectly and I have to switch the wires between pins 2 and 4.bobclausen — 09:24 AM
Philco 46-1209 strange behavior
No, it's not a problem, just during certain condition it could show up. Yes, an internal tube short could do that too. ...morzh — 09:13 AM
HiFi (Chifi) tube amp build - but my own design.
You sound guys are never satisfied. :crazy: :clap:RodB — 09:10 AM
HiFi (Chifi) tube amp build - but my own design.
I got some new ceramic octal tube sockets installed and also tried some different coupling caps.  The results:  The go...TV MAN — 08:42 AM
Philco 46-1209 strange behavior
I pulled the tube out and it's shorted from pin 1 to pin 2. I suppose that's the problem...sq65 — 08:12 AM
1949 Motorola 5A9M
bob  Nice work on battery . If you don't. Have terminals i have a few spares  Samsam — 02:12 AM
1949 Motorola 5A9M
hello mr Fixr, for sure !! I have some radios that I need to make some batteries for too. Sincerely richardradiorich — 12:33 AM
1949 Motorola 5A9M
Dittos, sweet b on the battery. Love the "9 Lives" logo, remembered from my childhood. Other neat ones are t...MrFixr55 — 11:24 PM
Philco 46-1209 strange behavior
Hi Morzh, Dunno if the AC EMI caps are an issue. I never liked the concept but never had an issue with these causin...MrFixr55 — 11:21 PM
Philco 46-1209 strange behavior
And no hum without the 7AF7? Not common but I am thinking heater - cathode short. This would introduce hum in this sta...MrFixr55 — 11:14 PM

[-]
Who's Online
There are currently 1325 online users. [Complete List]
» 1 Member(s) | 1324 Guest(s)
Avatar

>