Looking for EMT 250 Schematics/Service manual & Posibly repair

Hi,
I'm looking for some Schematics/Service manuals etc beyond what's in the user manual for an EMT 250 and possibly even an experience (with EMT 250's) repair engineer in London UK.
Anyone able to help ?
Thanks
Neil

Talk to David Kulka at Studio Electronics in Los Angeles. He knows all about 250s. He may know someone in UK. Or try Hebden Technology, he does Lexicons and might want to try a 250. They are not for the faint hearted.
Having said that, if you have no audio, check the LF356 opamps on the A/D and D/A boards, they are a weak point.

Thanks, I'm pretty sure (but not certain) David wanted $250 just for a copy of the service manual which it think was a bit OTT, We have audio passing fine but is very hissy/noisy, we've had years of re-flowing solder joints as they get toasty etc but our main guy who used to look after it has now retired and we were thinking to maybe get it looked at rather than battle it ourselves again.
Thanks for the lead on Hebden, I might get in contact with them.

Well, David is not a charity, and those schematics are big. From memory about 10 A1 sheets, plus the manual.

radardoug said:

Well, David is not a charity, and those schematics are big. From memory about 10 A1 sheets, plus the manual.

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I'm not suggesting he or anyone else is but selling someone else's intellectual property doesn't really justify any business case in my humble opinion.

Email address?

gyraf said:

Email address?

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I just PM'd you,
Cheers! 

I know David negotiated with EMT, and I also know they were very touchy about releasing drawings, so its quite possible he had to buy it. People sell IP every day. And bear in mind copying A1 drawings is not a trivial exercise. You have to find an A1 copier, drive there, wait for the copies, and drive back. Plus copy the other manual. How much do you think that would cost? So by the time David puts a profit on it, stores it, pays EMT, how much is it in reality? I get very tired of people like YOU, who dont want to pay for IP.

Well thanks for the school lesson there teacher but i'm not here for your self-righteousness, Selling IP is down to the copyright holder not anyone else. If he or anyone else is a licensee and paying a license to re-sell then that's up to him, And I as the potential client.
I have no information as to any license holding or right to sell on his part, so I'm not giving a penny for it without that upfront. In my experience people selling manuals and schematics are just on a money grab and have no legal right to sell the brand IP. if someone wants to prove they have the legal right to resell documentation I'll haply accept that as the case but i wont be buying it from anyone selling anything that's not theirs to sell in the first place and I'll get my information elsewhere thank you very much, there is always a way. We have 40 odd years worth of our own notes and drawings I'm just looking to make is a little more concise an cross checked.
I get very tiered of people like YOU who think they are the mayor of neckbeard town commanding righteousness behind their keyboard as if they are the arbiter of all things, when this has absolutely nothing to do with you. So maybe just mind your own business.  :-X

Really ?  $ 250,-- for something one can/could find on the web as .pdf (52 pages, 78MB) ?
How cool.....

Maybe could've negotiated some fat chewing sessions  as well...

oh wait....already out there...lol

https://www.sciencenc.com/pdfs/resources/elementary/chewthefat/ChewtheFatRules2018.pdf

analogguru said:

Really ?  $ 250,-- for something one can/could find on the web as .pdf (52 pages, 78MB) ?
How cool.....

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That is the manual, which does not include schematics for the main digital board. Thats the one with all the numbers sanded off.
So good luck with that!
DigitalMetal, thanks for the snarky message, but that wont mend your reverb. Its always good to piss off someone who could possibly help you.

radardoug you started the snark so you've got not basis to whinge.
For what it's worth, I have what I need now without your "help", if being a pita is what you call help I'd rather go without it thanks.
And again you are bahaving like a fool as if without your input I won't get the EMT repaired what a ridiculous ego you have.

For the EMT245, someone that I trust very much on the subject told me that the reason there is no documentation on the digital part of the circuit (the conversion/analogue/psu tec was leaked many years ago) was that that board was not even made by EMT/Bacho but was a piece of off-the-shelf military hardware from another OEM - with actual schematics classified.

This may very well go for the 250 as well, although I'm not entirely sure

/Jakob E.

gyraf said:

For the EMT245, someone that I trust very much on the subject told me that the reason there is no documentation on the digital part of the circuit (the conversion/analogue/psu tec was leaked many years ago) was that that board was not even made by EMT/Bacho but was a piece of off-the-shelf military hardware from another OEM - with actual schematics classified.

This may very well go for the 250 as well, although I'm not entirely sure

/Jakob E.

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Sounds plausible , i know Empirical Labs do it to guard their IP in the distressor (or at least used to) and its totally understandable for a product thats in current production or has commercial sensitivity but nobody in their right mind would go about cloning this beast one to one these days using old technology and other people like TC and UA have done their own versions so i dont think its such a case of IP for the product anymore but the military connection could be the sensitive aspect. Still doesnt explain why it would then be ok for someone else to sell the schematics because if anyone really wanted to exploit the military aspect $250 is a small price to pay  ;D
So either the sellers are not authorised and are just onto a fast buck or theres something very disjointed going on. Either way all that we in this group want is working gear that we love so hopefully we can achieve that with as minimal fuss possible.

as if without your input I won't get the EMT repaired what a ridiculous ego you have.

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To be fair, he did say "possibly" help you.......



As much as I enjoy a clash of the titans on some informative things , there are some rules here ...... Maybe a link to the info would make a nice finish to this thread....???....

..it's a 60mb pdf, that size not easily stored around here, thus the indirect approach..

/Jakob E.

There are about 20 D size (24 x 36 inch) sheets. Of that $250 about 1/3 is actual cost I need to pay to the print house for the copies and the rest is the time to trim, fold, and collate them, plus drive time. Throw in the inevitable technical questions that will come up, paypal fees, blah blah blah. Not a high profit item.

There are about 20 D size (24 x 36 inch) sheets.

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For actual prints this size on a classic piece of complicated gear would be worth owning when you service in the future.  If it’s for somebody else then I make them pay for the book.  For a pdf,  it seems high but keeping stuff alive keeps It usable.  And that’s the point if your into hardware uniqueness. 

Very good to know that the documentation really exist for the 250.    Are we so lucky that you also have the documentation for the EMT245?

/Jakob E.