stay at home type 69 project

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Nice project guys, a lot of great community spirit here too which is good to see.

That's a cracking job you did on those panels TwentyTrees, both the silver and the black from the company Ian recommended are very clear and look super easy to see where everything is when you're deep in the trenches on a session.

On the Amels buffer I'd posted a while ago: I agree that 100mA seems a little excessive for driving a 1:2 output transformer primary to +18dBu (so +24dBu on the secondary), but Dave Amels is no slouch when it comes to design and I'm inclined to think there was probably a good reason for him to waste power in those transistors - possibly they were more linear at higher current? Dunno? Anyway, easy enough to lower the current in the active sink and see what happens. Season to taste etc.

*Edit: got rid of the rest of my post which was just a bunch of yakkety yak nonsense 🙃
 
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One nice option for an adequate output driver for anyone doing a rev.3 (or whatever it's up to) module, would be to organize a group buy or something for the amplifier that Jim Dowler is using in his 500 series 'Olympic' mic amp/eq.
It could be used as an unmolested/naked pair for an electronic only output, or to drive a transformer. Or make it switchable between both options.

The link for the module is here:
https://audiodigitaltechnology.com/new_audio_digital_equipment/
And the page for the output 'Top Amp' is here:

https://audiodigitaltechnology.com/page-2/
 
My sincere apologies to all who attempted contact. I have experienced a good deal problems recently with Emails and hope they are behind me now.
Of course I am upset by the situation.
cyril_jones.com and [email protected] a both not active for some reason and will be corrected shortly.
My apologies once more.

Cyril Jones

Hi Cyril, thanks for you message.

Please check out the last 3 pages of this thread, people were contacting you for transformers, the developer was even thinking in changing the pcb layout and dimensions to accommodate your Lustraphone transformers.

https://groupdiy.com/threads/he-569-pre-eq-500-series.72521/page-5
Could you drop a post in the thread so that they know they can count you you?

Thank you so much
best regards
 
I've just posted a build report on the Helios mega-build I've been plugging away at for a while - gave it a separate thread so as not to clutter this one up:

Project Helios (ten "Type 69" in 3U)

Thanks again Matt for all your help and generosity! Thanks also to Ian for sharing so much insight about the Helios EQ over the years, and to Whoops for sharing the Musicland Helios docs.
 
I've built a few, so did TwentyTrees. I added schematics to the folder - thought they were in there, sorry about that. What questions do you have?
 
Hello all,
I have been trying to gather the parts for this awesome project and have been having a difficult time locating Grayhill 71ADF30-02PAJS switches. It seems like its out of stock everywhere these days… I was wondering if anyone had any idea where to find these? Or is there another Grayhill switch that can be used in its place? Thanks for all the help! This is such an amazing resource!
 
you can use a 71BDF30, which is 1/4” shaft. And if you drop the D from the part number, you may be able to find the switch with the right number of positions. Switches are really hard to find right now. :(
 
you can use a 71BDF30, which is 1/4” shaft. And if you drop the D from the part number, you may be able to find the switch with the right number of positions. Switches are really hard to find right now. :(
Thanks for the info! They have been very difficult to find…
 
I have a few things I have been struggling to figure out. I originally planned on ordering the H9M PCB with the output buffer that uses the 8 pin Jensen transformer but that transformer is out of stock for at least another 14 weeks. I contacted Cinemag about the CMMI-10 and still haven’t heard back on its availability as well… I have been able to locate the recommended Sowter transformer for the original H9 PCB but it doesn’t have an output buffer. Am I able to use the Sowter with the H9M PCB? Or is it possible to incorporate the output buffer with the H9? Or do you think I can get away with just building the H9 into a 500 series rack without the buffer?
Sorry for all the questions… I’m fairly new to this and this and having trouble wrapping my head around some of it. Thanks again!
 
It’ll work without the output buffer fine. Without it, it will struggle at very high levels into low impedance inputs - but in normal use no issue. Parts are a pain right now.
 
I'm thinking about building a pair of these - I'd like to use the original panel layout but the bass switch looks obviously not be a standard 30deg index angle switch. Does anyone know the specs of the original switch? I did find a 2 deck 2-23 pos switch that's a 15deg index angle but it's over $100! A bit too expensive to get one to just try it out.

Also does anyone know the dimensions of the original console panels?

here's the preliminary panel design I did in FPD for reference.

.fpe panel render .JPG
 
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Thanks! I'm hoping it had a 15 degree index angle - otherwise I can't find anything else even close.

I noticed there's a ton of variation on the panel designs in the consoles. I found yet another one I liked, So I made use of elements of my favorite parts of each.

Here's a Photoshop render of my semi-final version.
panel render.jpg
 
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