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

Vol control with tap
#1

Hello All.
I have a Firestone Model R-1661,
http://www.nostalgiaair.org/pagesbymodel...006273.pdf

The radio plays after restoration with the exception of the volume control ( #41A 250k ohm) which has some bad spots in it and I would like to replace it but the control has a Tap. Also the value of the pot is 500k so someone must have replaced it at one time.
Can I omit the tap?
Is there anyway to know the value of the tap or is it standard?
Is there a workaround I have a 250k pot I can use but it does not have a tap. 

Thanks Eric
#2

Eric
The tap on the vol pot is for slight equalization of the audio at low volume.  It rolls off the high frequencies a little at low volume.

On the old stereo receivers it could be switch in or out. It was called "loudness contour". 

Using a volume pot without it if you don't like the sound you could add a cap of similar value at the high side  and change it's value to suit your tastes. You may not even notice any difference unless you are listening for it.

!!!!!!!!!!!!!!!!!!!RESISTANCE IS FUTILE!!!!!!!!!!!!!!!!!!!!!!  
                           /\/\/\/\/\/\/\/\/\
                                                     
                                 [Image: http://philcoradio.com/phorum/images/smi...on_eek.gif]  Chris
#3

Hello Eric,
I would Give Mark at https://www.oldradioparts.net/
He repairs controls he has lots of them .

Sincerely rich
#4

My late father in laws Zenith with a tap on the volume control that had been replaced in the past. After a recap and a few resistors replaced the radio played fine. The repair shop placed10 turns of wire from what would be the the tap feed around the in coming signal to the control. The repair was made in the time frame of 1968-1975.
#5

So I played around with it and put in a 250k pot I had and left the tap lead off and it played fine but I also needed a switch for power so I looked in my box of stuff and came up 500k w/switch and put that in just to see what would happen and it actually played better than with the 250k pot.

 I have bought from Mark Oppat before but I also don't know the value of the tap. Is standard value?

Thanks 
Eric
#6

Hello eric,
Sure thing .

Sincerely Rich




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
An attempt to remove the Field Coil from a G speaker
Mike; I've made a one or two spiders by using some card stock, and a razor blade, it took more then one try but they ...Arran — 05:48 PM
Philco 91 Restore Code ??
I wondered about that. Wish there was some place local to get this stuff.dconant — 04:20 PM
Philco 89 indicator light.
Bending the lamp bracket (moving the lamp, that is) can possibly change the shape of the pointer a bit, but not its loca...morzh — 04:01 PM
Philco 91 Restore Code ??
Because the usable power rating of it hen is (3,200/20,000)*25W= 4W. Maybe a tad more due to the mass, but not much. Yo...morzh — 03:59 PM
Philco 89 indicator light.
Thank you Dan, that was the trick. I kept trying to rebend the lamp bracket but that wasn't doing anything to help.Jim Dutridge — 02:18 PM
Philco 91 Restore Code ??
20K 25 watt. I thought it was a 20 watt at first.dconant — 01:37 PM
My Philco 37-116 Restore
Nah, too much and not that important.morzh — 01:33 PM
Philco 91 Restore Code ??
What's the full value of that resistor?morzh — 01:31 PM
Philco 91 Restore Code ??
Been running the radio for three hours now. The power transformer has settled out at 140 degrees. The filter choke is ab...dconant — 12:38 PM
My Philco 37-116 Restore
Parts-express.com has them for around 5 bucks and up. You can probably get them on Amazon too.RodB — 11:48 AM

[-]
Who's Online
There are currently 3297 online users. [Complete List]
» 2 Member(s) | 3295 Guest(s)
AvatarAvatar

>