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

Resistor substitution question:
#1

I’m working on a couple of old Philcos, 37-84 and 71B.  Need to order some resistors.  Problem is, when checking some of the vintage parts suppliers, the resistors they stock are not within 10% of the values I need.  As an example, I need a 6k and 13k but the closest they list are 6.8k and 12k-15k.  I could probably order from one of the major parts suppliers but I would prefer to deal with our “vintage radio” guys.  I guess the bottom line is, can I safely assume 20% tolerance or stay within the 5 to 10% norm?  I’ll probably go with 1w if available.

Thanks!
Hokep61
#2

Original spec was 20% so your fine. Most of them are going to be 1/2w, the ones that like 3/8 in dia are 3w. Rule of thumb is that for the most part the higher wattage resistor are going to in the power supply circuit and in the cathode circuit of the output tubes. The two power resistors in the hv on the 84 are 2w. Size wise resistor have gotten alot smaller in size but can dissipate the heat well.

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
#3

Thanks Terry for the reply and info. Wasn't sure of the tolerance of the old resistors.

Hokep61




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
462ron
It’s on the bottom of the homepage of our Philcoradio.com homepage! Ron462ron — 07:20 AM
Model 70 Cabinet Trim
Steve might have some trim left. Not sure he is making anything.morzh — 06:12 AM
Model 70 Cabinet Trim
Hello musar, First all welcome to the forum and yes that is true that steve stopped making trim . Sincerely Richar...radiorich — 12:13 AM
Model 70 Cabinet Trim
I have recently come into possession of a Model 70.  The trim around the base needs to be replaced.  If this were years ...musar — 12:07 AM
philcorepairbench.com - shadow-meter
Anyone know of a way to recover these files from the repair bench? Thanks. fenbach — 11:16 PM
Philco model 38 code 121 not receiving signal.
That's true. Of course If I were to get a vtvm I'd probably have to sink money in to it to get it working right. Probabl...Stormlord5500 — 08:44 PM
Philco model 38 code 121 not receiving signal.
A DMM is good enough. One rarely has to measure indictance, but if you do, short of getting a serious LCR meter (I hav...morzh — 07:35 PM
Testing a speaker and output transformer Trutone A2-G
You guy's are right on. I found a broken wire on the speaker plug that I replaced and all is well now. Have better volu...murf — 03:43 PM
Philco model 38 code 121 not receiving signal.
I need to get a vtvm. I think that little component tester is just more accurate. Plus it shows the inductance which is ...Stormlord5500 — 03:07 PM
Philco model 38 code 121 not receiving signal.
I use a pair of Mastercraft brand DMMs from Canadian Tire, from what I read most of those DMMs use the same main chip re...Arran — 02:36 PM

[-]
Who's Online
There are currently 239 online users. [Complete List]
» 1 Member(s) | 238 Guest(s)
Avatar

>