deconstructing Dear Prudence

[Winston OBoogie]

I am sure you guys have seen this...

Correct link : Stephens Tape Recorder Schematics & Notes

Yes I've seen those. What isn't included (unless I missed it) is a schematic of the little plug-in amps (618 & 620 etc.) because, as far as I could determine when I looked through the extant documents from Stephens' estate, John Stephens didn't draw schematics for them.

My recollection of the story is that there was only one lady, Mary, who was trained to make the amp modules for him.


There is no pcb inside, everything being point-to-point resistors and transistors, with teflon tubing for insulation around the leads to prevent shorts etc. There wasn't a whole lot of room inside those cans to get everything wired together, and I wouldn't want to attempt makin' 'em myself.

The only reason I was able to reverse engineer the things was because, along with some tape machines, parts, and documents etc., Audities also had Mary's work bench items and there were a few modules in various states of completion.

I have no desire to keep the schematics hidden and I'd happily publish if it were just my decision.
But I don't know the situation with Audities as far as them wanting to keep the things under wraps.

Best thing to do would be to contact David Kean @ Audities Foundation.

Otherwise, plenty of other discrete circuits to play with so it's not the end of the world

 

[groselicain]

Correct link : Stephens Tape Recorder Schematics & Notes

Yes I've seen those. What isn't included (unless I missed it) is a schematic of the little plug-in amps (618 & 620 etc.) because, as far as I could determine when I looked through the extant documents from Stephens' estate, John Stephens didn't draw schematics for them.

My recollection of the story is that there was only one lady, Mary, who was trained to make the amp modules for him.


There is no pcb inside, everything being point-to-point resistors and transistors, with teflon tubing for insulation around the leads to prevent shorts etc. There wasn't a whole lot of room inside those cans to get everything wired together, and I wouldn't want to attempt makin' 'em myself.

The only reason I was able to reverse engineer the things was because, along with some tape machines, parts, and documents etc., Audities also had Mary's work bench items and there were a few modules in various states of completion.

I have no desire to keep the schematics hidden and I'd happily publish if it were just my decision.
But I don't know the situation with Audities as far as them wanting to keep the things under wraps.

Best thing to do would be to contact David Kean @ Audities Foundation.

Otherwise, plenty of other discrete circuits to play with so it's not the end of the world

Not to derail the conversation, but I remember only just becoming aware of Audities when we were discussing the Strawberry Helios. What an unreal collection they have.

 

[ruffrecords]

Correct link : Stephens Tape Recorder Schematics & Notes

Yes I've seen those. What isn't included (unless I missed it) is a schematic of the little plug-in amps (618 & 620 etc.) because, as far as I could determine when I looked through the extant documents from Stephens' estate, John Stephens didn't draw schematics for them.

There is one scrappy hand drawn schematic that says 618 on it.

Cheers

ian

 

[Brian Roth]

The Waltzing Bear collection is amazing. Wish I had it in times past when working on the two 40 track machines originally owned by Leon Russell.....not that I had much trouble with them.

One of the two machines worked quite well, the other was a bit of a mess and mainly an "organ donor". The main machine was being used to transfer Leon's 2" 40 track tapes into high res digital. It was two years ago when I last worked on the machine. The -39VDC audio supply had died. After repair of that, one channel (30-something) wasn't playing back. I was very worried that it was a bad coil in the playback head, but thank goodness (?) sync playback on that same track was also dead.

Did a lot of swapping of audio electronics, relays, and my best guess was something haywire in the cable harness/connectors. BUT.....no decent docs for that portion. I imagine I could have spent days/a week blindly probing around with a DVM to try and reverse engineer the cable harnesses and connectors. I had been down that rabbit hole with transport control wiring in years past (although that only took a day since I had a few schemos).

Last I heard, the non-profit group behind the Leon tape transfer project had crated both machines and shipped them to Audities for them to repair/refurb. I'm sure the failure and repair is simple for someone with all the docs, so I'm not embarrassed since I was flying blind.

Bri

 

[Winston OBoogie]

Edit: Ian, taking a look, the scrappy drawing isn't mine, I think I see a 1967 date on it but ?

Maybe the story I was told regarding John not drawing out the schematic wasn't true after all?
Anyway, what I drew is the same as this schematic so it looks like I properly de-coded Mary's little bundle of tangled spider legs and dead-bug wiring.


Brian, I wouldn't feel bad at all about not being able to find the issue, without documentation those wiring harnesses of his would be a real challenge
From talking with folks who knew John or had bought machines, I think a lot of the specific info regarding the maintenance was kept in his head. If you lived in L.A. then you'd probably be OK as he would come over and fix the machine if it went down in a session. Otherwise, not sure how stuff got dealt with out in the field.

If anyone has info that'll get Leon's machines going again it'll be Audities so they went to the right place

 

[Brian Roth]

One of my oldest best friends/clients (now RIP) was doing the Leon transfers. The Stephens machines are part of Leon's estate. My friend was also "caretaker" of a huge mountain of Leon's gear even before Leon passed away. Yes, Leon was a serious "gear head"! 10-ish years ago a huge "Allied Van Lines" type of moving truck was filled with the gear and moved from Nashville.

My friend told me a story he heard from Leon when they were working together years ago....so it's not known to me as an actual fact.....someone told someone who told......

John wouldn't supply full docs for the machines, so Leon took him to court. I guess Cali had some sort of "right to repair" laws decades ago. Stephens coughed up some info which was what I had to work with, and it was cryptic and incomplete.

Even further back, my friend helped "broker" the sale of Leon's Red wraparound 40 channel Helios desk. I think it went through Audities before Lenny Kravitz bought it...and Lenny changed the front panels from red to black!

I actually had an hour or two to examine and poke around with the Red desk. I pulled some modules and took a peek. I'll just say I was not particularly impressed with the choices of things like the pots, switches and internal construction. I know that is "heresy" to the Helios fanboys, but at the time my friend had a Neve 8068 desk in his studio which was awesome in terms of construction, component selections and attention to detail. It was "apples vs. rutabagas" to me. <g>

Bri

 

[ruffrecords]

Edit: Ian, taking a look, the scrappy drawing isn't mine, I think I see a 1967 date on it but ?

That's the one. I don't know about you but I was 17 in '67. Great time to be a teenager.

Cheers

Ian

 

[Brian Roth]

That's the one. I don't know about you but I was 17 in '67. Great time to be a teenager.

Cheers

Ian

Was a great time for me as well at age 13!!!! So many great songs on the radio.

Bri

 

[Winston OBoogie]

That's the one. I don't know about you but I was 17 in '67. Great time to be a teenager.

Cheers

Ian

I was 1 in '67, I was probably having a great time too

 

[Gold]

I was 1 in '67, I was probably having a great time too

I was more than zero but less than one in 1967. Living in East Harlem with the folks. I bet that was quite a scene in 1967.