Tazin---> Thanks for the heads upTazin wrote:For a rough date of manufacture you could read the date codes on the pots, and the serial number on the motor.
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Cheers,
Eric
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Tazin---> Thanks for the heads upTazin wrote:For a rough date of manufacture you could read the date codes on the pots, and the serial number on the motor.
Congrads great info to know!Myopic Void wrote:Tazin------------------------->GOOD NEWS! I have dated them. My #1 is a 1971 and my #2 is a 1974. They are both Chicago Telphone Co. (CTS) pots.
Their code is 137. It goes like this 137 (CTS), 71 year, 30 week. 1377130
Hat's off to you Tazin![]()
I always wanted to know exactly what years and now I know. #2 is older than I thought 1974 and #1 1971 is right at the very beggining!
Cheers,
Eric
Atomic----Thanks, it's great finally put the mystery to rest! I feel stupid for not thinking of thisAtomicChunk wrote:Congrads great info to know!Myopic Void wrote:Tazin------------------------->GOOD NEWS! I have dated them. My #1 is a 1971 and my #2 is a 1974. They are both Chicago Telphone Co. (CTS) pots.
Their code is 137. It goes like this 137 (CTS), 71 year, 30 week. 1377130
Hat's off to you Tazin![]()
I always wanted to know exactly what years and now I know. #2 is older than I thought 1974 and #1 1971 is right at the very beggining!
Cheers,
Eric
btw is that a Royer R-121 on your cab!?
Myopic Void wrote:Atomic----Thanks, it's great finally put the mystery to rest! I feel stupid for not thinking of thisAtomicChunk wrote:Myopic Void wrote:Tazin------------------------->GOOD NEWS! I have dated them. My #1 is a 1971 and my #2 is a 1974. They are both Chicago Telphone Co. (CTS) pots.
Their code is 137. It goes like this 137 (CTS), 71 year, 30 week. 1377130
Hat's off to you Tazin![]()
I always wanted to know exactly what years and now I know. #2 is older than I thought 1974 and #1 1971 is right at the very beggining!
Cheers,
Eric
Congrads great info to know!
btw is that a Royer R-121 on your cab!?![]()
Mic's...yes it's a Royer 121 and a June 1970 Nuemann U87.
Cheers,
Eric
Great info. Thanks!Tazin wrote:For a rough date of manufacture you could read the date codes on the pots, and the serial number on the motor.
Hey TJ,T.J.Fuller wrote:Great info. Thanks!Tazin wrote:For a rough date of manufacture you could read the date codes on the pots, and the serial number on the motor.
couldn't find a serial no. on the motor but, the pot ID ...hell yeah!
my Ep-3 dates at 1976- serial #28255
Eric,
you mentioned you have 2 Ep-3's with one being brighter than the other.
Is the later model the brighter of the 2 ?? and does it have greater gain?
There is a resistor that is 250K on earlier models vs. 100k on later models, going to the echo mixer section.
This would have an impact as far as output.
there are capacitor differences on earlier models versus later models.
The which unit is brighter info. - would be greatly appreciated, if you happen to read this post.
TJ---> if you can do some test that would REALLY help. I can't wait to see what you find out regarding resistors and brightness. I want to get these two EP3's on the same page.T.J.Fuller wrote:I'll post the differences in schematics later when I get home.
The resistor shouldn't effect the brightness, however it's a unique circuit.
but, from the schematics I have , the cap before 1st. transistor would and I think there is a bypass cap. difference in the circuit as well, other than the motor.
I have had mine apart recently and I'll be experimenting shortly.
...might be best to let me swap some stuff first, I'll share the results.
I'll still list what is different later.
but, I have the FULL Echoplex manual w/ all the schematic variations on all models and years , even the sireiko echoplex version on PDF.
PM me if you would like it.
Motor has this # Tazin...11FA 75981 Universal. How can you read this code?Tazin wrote:Glad I could help....
I've got a copy of an original Market Electronics Co. schematic for the revision 2 model EP3 [Serial numbers 9451 to 12960] which is dated January 12, 1971. There's a good chance that revision 2 started around that time frame.
Kinda surprised there was no serial number on the motor?.......The one I have carries this: 8GA 77275.
TJ I prefer the brighter 1971. The 74 is a lot darker. It would great to understand why and possibly brighten it up a tad.T.J.Fuller wrote:TIS58 because it is a JFET the drain and source can be interchanged
it is the gate or base that if hooked up wrong that would be an issue.
There are some obsolete electronic suppliers still sitting on stock of these transistors even though they are no longer being made.
**EDIT- I just checked mine, all 3 on that board are flat side facing left
Eric, from what you posted, you prefer the brighter sound EP3..correct??