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

Philco 90: expecting too much?
#10

Ron Ramirez Wrote:Yes - 1000 ohms/volt was the standard for many years. 20K ohms/volt is much better, and the modern DMMs are in the 1 meg/volt or better range.

Just to clarify Very old volt ohm meters were 1K per volt. I would suspect these where used for testing B batteries. The meter would load the battery and give better more accurate reading under a load and 1000 ohms would do it. Most radio circuits you don't want to load. It will give you an inaccurate reading. Later I'm guessing late 1920's better vom's 10k and 20k per volt. Vtvm ( vacuum tube voltmeter) and Dmm (digital multi meter) all are 1meg per volt or better (higher). Personal preference is use dmm for resistor. Very accurate. Use vtvm for voltage. Two reasons: 1 Problaby what was use when set was made to measure the voltages that are on the documentation. 2 Dmm's sometimes can give an incorrect reading. They are sensitive to any sort of signal that maybe be mixed in with the voltage you are measuring. This happens a lot with measuring voltages on TV's and things like ham transmitters. This can be very frustrating!!!
I'm jumping off my soap box.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry


Messages In This Thread
Philco 90: expecting too much? - by Guest - 02-05-2010, 01:28 AM
Re: Philco 90: expecting too much? - by Guest - 02-05-2010, 08:41 PM
Re: Philco 90: expecting too much? - by Guest - 02-06-2010, 11:34 PM
Re: Philco 90: expecting too much? - by exray - 02-07-2010, 09:48 AM
Re: Philco 90: expecting too much? - by 7estatdef - 02-07-2010, 04:01 PM
Re: Philco 90: expecting too much? - by 7estatdef - 02-07-2010, 04:19 PM
Re: Philco 90: expecting too much? - by 7estatdef - 02-07-2010, 05:07 PM
Re: Philco 90: expecting too much? - by codefox1 - 02-07-2010, 05:45 PM
Re: Philco 90: expecting too much? - by Guest - 02-08-2010, 12:27 AM
Re: Philco 90: expecting too much? - by 7estatdef - 02-08-2010, 08:59 AM
Re: Philco 90: expecting too much? - by codefox1 - 02-09-2010, 06:31 PM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
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
schematics
Those filter caps in the cardboard tube are easy to restuff, especially the kind with the rolled over end. You don't hav...Arran — 09:56 PM
Philco Model 16 wiring question
If you have 5 wires, do this: The wires that go to thick-wire wound winding are the filament. If you do not know wha...morzh — 09:03 PM
Philco Model 16 wiring question
I recently acquired a Philco Model 16 Code 126. I removed the power transformer to place heat shrink on some very bad...bobclausen — 08:23 PM
1949 Motorola 5A9M
Hello Bob, That battery looks great nice job ! Sincerely Richardradiorich — 08:20 PM
1949 Motorola 5A9M
Yes, I plan to put a Velcro closer on the top.klondike98 — 07:28 PM

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

>