Intro and an Obscure Amp?

Tube and solidstate amplifiers made by Rickenbacker

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TelecasterTech
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1961 RICKENBACKER EK-O-SOUND M-30 - RESTORATION - PART 13

Post by TelecasterTech »

F
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tape33.jpg
tape34.jpg
tape35.jpg
tape36.jpg
TelecasterTech
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Controls, Trannies, and Ground wire

Post by TelecasterTech »

Figured this might be handy for people, since I've been asked so many time for this.

Cheers!!

Frank
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M30SCHEMATIC - CONTROLS.JPG
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doctorwho
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Re: Intro and an Obscure Amp?

Post by doctorwho »

Great photodocumentation, Frank!

I'm glad to see that the one on eBay got into good hands.
It is better, of course, to know useless things than to know nothing. - Seneca
TelecasterTech
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Doctor Who Made This Possible

Post by TelecasterTech »

Hi Doc,

Well, it was your post on this very thread, page 1, Tue Oct 05, 2004 2:52 pm, that really got me looking into the patents and digging through the Internet. And after that, you had sent me the patent number, and it took off from there.

All the information provided herein is presented to all as a token of my appreciation for your help with this obsession of mine.

Cheers!

Frank
TelecasterTech
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WARBLY TREBLE FIXED - ECHO TAPE DELAY BOARD

Post by TelecasterTech »

Hi all!

For those of you still following or interested, and perhaps also some others out there with similar symptoms, my tape echo had a problem following the restoration project: the treble notes sounded warbly (bass notes were great!).

So I found 2 proper idler wheels from ebay (WALSCO # 1432), and I decided to install them this weekend. While I had the tape board out, I performed other maintenance steps that I felt might make the warbly treble note problem go away. Well..... IT DID.

Here's what I did:
1 - changed the idler wheel - In my photos, you can see the comparison between my old worn one and the 2 new ones.
2 - made a longer tape loop, now it's not so tight (slides better.? Less strain on the motor/wheels.?)
3 - cleaned new ldler wheel and pinch roller with Rubber Renew chemical (I had already done this when I restored the amp)
4 - tightened the screwn that allows the idler wheel MOUNT to pivot freely (you can see this in my photos.. the part with lots of green grease on it)
5 - cleaned PLAY REC & ERASE tape heads (I had also already done this when I restored the amp, but maybe got dirty during preliminary tests)
6 - used alcohol to clean the motor's spindle, the aluminum drive wheel, and all tape retainining posts/wheels
7 - loosened tension on spring that holds the pinch roller solenoid, so that, when not active, the rubber pinch roller doesn't spin anymore (not rubbing the tape)

THE AMP SOUNDS SO GREAT NOW THAT I WANT TO BUILD MYSELF A SECOND ONE TO PLAY IN STEREO!! :-)

Please enjoy the photos &:-)

Cheers!
Frank
aka Guitarsmith
Attachments
Idler Wheel mount & pivots.jpg
Idler Wheels - edge wear.jpg
Original Idler Wheel & 2 replacements - top.jpg
Tape Board - Cleaned.jpg
TelecasterTech
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Re: Intro and an Obscure Amp?

Post by TelecasterTech »

(Argh! those Selmers apparently didn't sound too good...but they are appealing to the eye. Eddy Cochran couldn't stand to use them....)


So here's yet another post on this thread, not sure who's still following. But for history's sake, here's the direct full color scans of the tape delay board. I took everything off of mine, and scanned it into my computer and made 2 photos from the scans - one's the top view and one's the bottom view.

Since the photo file is exact size, this forum would not accept the size of the pictures, so I've ZIPed them together in 1 files - use WinZip or something like that to unzip the file and get the photos.

The top view wil help you see where the screw holes go. The bottom view is rather boring, but you can still see the holes where one could access the tape head nuts that hold them in place.

The board is 3/4" thick plywood, 9" wide, and 20.2" long.


Hope this helps anyone looking to make a replacement for themselves.

Frank
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TapeBoard.zip
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jingle_jangle
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Re: Intro and an Obscure Amp?

Post by jingle_jangle »

Brilliant!!!

Thanks, Frank!

Anyway we can solidly document this sort of thing before it disappears into oblivion, is a big PLUS in my book. :)
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brianjose
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Re: Intro and an Obscure Amp?

Post by brianjose »

How do you get the patent number? The USPTO site allows only Patent Number and you just cannot access the site to find out the number.
If you are applying for the first time patent application for your invention then filing date is very important for several reasons. here are few more details.
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doctorwho
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Re: Intro and an Obscure Amp?

Post by doctorwho »

brianjose wrote:How do you get the patent number? The USPTO site allows only Patent Number and you just cannot access the site to find out the number.
Brian, thank you for bringing this thread back to life! :)

A significant thing has happened since my initial patent search. The website Free Patents Online (http://www.freepatentsonline.com/) was created and it allows full search term searches of the entire collection of US patents (including pre-1975) .

I just did a search on "JOSEPH RAYMOND BUTTs" (the inventor), and lo and behold, patent # 2804499, Reverberation method and apparatus, showed up in the search results!
EchsonicPatent_cr.jpg
Hip Hip Hooray!

The pickup patent (#2892371) mentioned above was also there in the search results:
ButtsPickupPatent_cr.jpg
One can download the pdf file of the patent for free at FPO.

Now that we have the elusive patent number, we can use it at the USPTO site to do additional research.
It is better, of course, to know useless things than to know nothing. - Seneca
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8mileshigher
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Intro and an Obscure Amp?

Post by 8mileshigher »

This thread is pretty fascinating reading, about a little niche in amplification-technology history ..... :)
TelecasterTech
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Re: Intro and an Obscure Amp?

Post by TelecasterTech »

brianjose wrote:How do you get the patent number? The USPTO site allows only Patent Number and you just cannot access the site to find out the number.

It is also stamped " PAT 2804499 " in black ink, into the back of my Rickenbacker amp, on the bottom lip of the cabinet underneath where the tape board goes :D :idea:
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PATENTSTAMP.jpg
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