I've found the volume pot, that was tricky since this radio has volume and tone on the same shaft. But by measuring the resistance I could see it change on the "back" pot when I turned the volume knob, without power of course.

I can see 5 taps off the volume pot, but I cannot get the guitar to play when I tap off of any of them. Here's what I have.

Tap 1 has 9v when the volume control is clicked on, 0v when off.  Tap 2 has 9v all the time.

On the bottom we have 3 more taps.

Taps A, B and C also have 0v when the volume is off, and 9v when the volume is on.

I pull the batteries and measure resistance (and yeah, I know, the pot is in the circuit so it isn't accurate but I'm just trying to find the "input" lead.

A always reads 4k Ohms, B varies from 2k to 4k, C is at 2k no matter what I do with the volume knob.

1 in always at 2k Ohms, 2 is 0 Ohms when off, 2k when on (which makes sense since it is connected directly to the battery)

So it seems to me that I should be hooking into tap B. So when I hook the rod-piezo to B and to ground I still hear the static of the radio and when I pluck the string, I do not hear the note out the speakers.

All the online tutorials make this look easy, but I'm baffled at this point.

Views: 485

Reply to This

Replies to This Discussion

I'm no electro guru, and someone else might help more, but, i think term B will be signal out, so you still have the radio going, even if you connect the guitar to there, I would guess, terminal A is currently radio input to volume pot, and you would need to connect there and either add a switch to change from radio- guitar, or just disconnect radio totally . Looking at your pic again, it could be that A is ground as it appears it might be 1 piece with the terminal strip going to the rear, but hidden by the other component. I've probably confused you more than helped you, but someone will set you straight


i think this is what you are trying to do. i think that volume pot is between the preamp and power amp sections. your rod piezeo doesnt have enough to drive the amp section and you havent isolated the Rf or radio section.  radio was not my field in electronics so i only have basic knowledge. 

I tried a 3-pole magnetic pickup just now. No joy.

And how can I isolate the RF section? I'd love to not hear the radio...

If this is the layout, wouldn't it be better to disconnect the RF stage signal and make the wires to the preamp into the new input? Assuming it's not high voltage.

It isn't high voltage. I don't mind doing that but I don't know how.

Lugs 1 & 2 on the back are the on/off power for the radio.

Lugs A, B, & C on the bottom are probably power on circuits to the rest of the components since they have a 9volt reading.

What about the 3 lugs on top with a cap? Trace those 2 wires coming off the top and get a volt reading on them.

The three lugs with the cap are for the tone control, but I just tried it. No joy.

Silvertone, from 1961- or 1962

I'll run the resistance test right now.

There are two lugs on the tone pot. (The third is just stick up in the air, not attached to anything.) One of them varies the resistance from 0 to 40k Ohms when I turn the tone pot. The other is ground.

The resistance does not vary with the volume knob turning.

Showing TR6 and TR7(3 stage pot area) for Audio Output. So 1 of those stages has to be volume.

Does the radio work? just wanted to be sure before going further.

TR1 area looks to be the area to find the preamp, that should be the area for the guitar input. Snap a good pic of the board for me if you can.

It works just fine.

RSS

The Essential Pages

New to Cigar Box Nation? How to Play Cigar Box GuitarsFree Plans & How to Build Cigar Box GuitarsCigar Box Guitar Building Basics

Site Sponsor

Recommended Links & Resources


Forum

crossover guitar.

Started by Timothy Hunter in Other stuff - off topic, fun stuff, whatever. Last reply by Timothy Hunter Mar 21. 11 Replies

Tune up songs

Started by Ghostbuttons in Building Secrets, Tips, Advice, Discussion. Last reply by Timothy Hunter Mar 9. 5 Replies

Duel output jacks

Started by Justin Stanchfield in Building Secrets, Tips, Advice, Discussion. Last reply by Taffy Evans Mar 8. 6 Replies

How to Get Your Own Music on Spotify

Started by Cigar Box Nation in Feature Articles. Last reply by Southern Ray Feb 21. 2 Replies

CB Bass Guitar

Started by Mi Rankin in Building Secrets, Tips, Advice, Discussion. Last reply by Justin Stanchfield Jan 27. 5 Replies

Latest Activity

BrianQ. commented on Dar Stellabotta's video
1 hour ago
BrianQ. liked Dar Stellabotta's video
1 hour ago
Southern Ray commented on Southern Ray's photo
Thumbnail

Project Punch!

" Thank ya again Keith!"
3 hours ago
Southern Ray commented on Southern Ray's photo
Thumbnail

Punch Project!

" Thank Ya Keith!"
3 hours ago
Doug Thorsvik commented on AGP #'s photo
Thumbnail

AGP #527 - ''Led-Zep 2''

"This build really strung you along Alan! Reminded me of all my fishing line experiments; a lot of…"
5 hours ago
Doug Thorsvik commented on A.D.EKER's video
Thumbnail

Im Troubled (Tribute) Mc K Morganfield by BCB - A.D .Eker 2024.

"Diggin’ the slow blues. I like that last pic Andries! Look at all those cool guitars. Yeah!!!"
5 hours ago
Dar Stellabotta posted a video

A Cigar Box Guitar Six Stringer Built by Louie Lamanna

This video is the unboxing and the demonstration of a beautiful, six stringer built by Louie Lamanna. Join Louie and I June 15 at the second annual Pittsburg...
6 hours ago
Doug Thorsvik commented on Doug Thorsvik's video
Thumbnail

Hail the Resurrection Day: 2-String Violin Chugger Cigar Box Guitar

"Happy Easter to you too Andries! The passion is definitely in full swing. Turns out I’m…"
7 hours ago
A.D.EKER commented on Doug Thorsvik's video
Thumbnail

Hail the Resurrection Day: 2-String Violin Chugger Cigar Box Guitar

"Happy Easter Doug ! the Passion is in full swing !"
7 hours ago
A.D.EKER commented on Ricky D's photo
7 hours ago
A.D.EKER commented on A.D.EKER's video
7 hours ago
Keith Rearick liked Doug Thorsvik's video
11 hours ago

Music

© 2024   Created by Ben "C. B. Gitty" Baker.   Powered by

Badges  |  Report an Issue  |  Terms of Service

\uastyle>\ud/** Scrollup **/\ud.scrollup {\ud background: url("https://storage.ning.com/topology/rest/1.0/file/get/963882636?profile=original") no-repeat scroll 0 0 transparent;\ud bottom: 25px;\ud display: inline !important;\ud height: 40px;\ud opacity: 0.3 !important;\ud position: fixed;\ud right: 30px;\ud text-indent: -9999px;\ud width: 40px;\ud z-index: 999;\ud}\ud.scrollup:hover {\ud opacity:0.99!important;\ud}\ud \uascript type="text/javascript">\ud x$(document).ready(function(){\ud x$(window).scroll(function(){\ud if (x$(this).scrollTop() > 100) {\ud x$('.scrollup').fadeIn();\ud } else {\ud x$('.scrollup').fadeOut();\ud }\ud });\ud x$('.scrollup').click(function(){\ud x$("html, body").animate({ scrollTop: 0 }, 600);\ud return false;\ud });\ud });\ud \ua!-- End Scroll Up -->