Klein + Hummel UE-100

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DaveP

Well-known member
Joined
Nov 8, 2005
Messages
3,019
Location
France
Has anyone ever checked the voltages on this tube EQ?

There are four power supplies,:-

DC supply for the heaters.

B+ high voltage supply.

Second B+ used with the negative supply.

A negative supply.

Any info appreciated

DaveP
 
Have you looked at the schematics on my site somewhere?

It's built around a handful of tube differential amplifiers (ECC81+ECC83) running on +/-150V

/Jakob E.
 
Yes,Jacob  I have the schematics but no voltages.  Are they exactly +/- 150V ?

The other one is probably 300V/250V and not critical

Thanks for that

DaveP
 
That's what I found at the Drip manual:

1. negative bias @ - 100v
2. low plate @ +100v
3. high plate @ +300v
4. 3.6 amp heater supply for ch1
5. 3.6 amp heater supply for ch2
6. relay power supply (adjustable)

If it would be any help for you I can send you the Manual.
Around page 47 the PSU is described

Greets
Sebastian
 
Pusch31 that would be very kind of you, I'll send you a PM.

@Gold, yes I've seen them, they look great, but my friend wants me to make him one!

Best
Dave
 
The hard parts - other than the in/out iron - are

1) the big switch banks and

2) the zero-tempetature-coefficient precision timeconstant capacitors for the filters. These are simply made from two parallelled capacitors of some styrene origin - but one has a positive temperature constant where the other has a negative.

I will still claim that whoever designed this beast would probably have been happier just taking the perscribed OCD medicine..

The electronics pusher "Reichelt" in Germany has decently-priced E83F and 6201 (E81CC) type tubes.. Just sayin.. :)

/Jakob E.
 
Thanks for that Jacob,  I would use rotary switches.

Any idea on the IPT and OPT ratios?

DaveP
 
DaveP said:
Thanks for that Jacob,  I would use rotary switches.

Rotary switches are fine for everything except the two bandpass sections. Technically rotary switches will work.  The center section is confusing enough from an operators point of view because you aren’t setting the center frequency. You are setting the bandwidth. The graphic shows the center frequency for a given bandwidth.  I can’t think of a way to make that clear with rotary switches.

My favorite part of the UE100 is the high and low shelves. I would be happy with just those two sections.
 
I will still claim that whoever designed this beast would probably have been happier just taking the prescribed OCD medicine..
Half the people on this forum should take this advice ;D ;D ;D ;D

Thank you Jacob, Gold and Sebastian for your good info, I now have the info I need for next years project, but much more research still to do on the switching............ a handy self-isolation project? ::)

If this project does not appear next year "UE-100 from scratch",  it will be because the virus has got me.!  But as we used to say, "Carry on regardless",  ;)

DaveP
 
It's possible to do this using rotary switches, as only one step is active at one time. I was looking deep into this at an earlier point where I had a lot of time at hand.

Please note that for the mid frequencies I think you'd need at least a quad-deck switch.

Here's a pic where the double-stacked capacitors are shown clearly:
 

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..and here the front panel layout we have reached so far - although we've only been through the first 20-25 revisions: For UI logic and functionality, it's seems best to group db/freq/function switches like this, to prevent end user quickly loosing track of what he's doing:

Levels at the top
Functions in the middle and
Frequencies at the lowest row

/Jakob E.
 

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Thank you Jacob for those tips and I had come to the same conclusion about needing a couple of 4 Pole  8 way  wafer switches.

Best
DaveP
 
Remember that you're not under any obligation of sticking to 8 frequencies if you have 11 stops on your switch.

And even more important, the boost/cut amount does not have to start at 2dB or nothing - it would make a whole lot of sense to make the first steps ½-1-1.5dB and then interpolate the rest over the rest of the positions..

/Jakob E.
 
gyraf said:
..and here the front panel layout we have reached so far

For the mid frequencies I see how the dual rotary switches replicate the function of the switch groups. It doesn’t give you an indication of center frequency which I would find massively confusing. It’s not a UI that exists anywhere else. The switch groups are confusing. This  arrangement is a manual reader. 
 
Just to put this on the record............

There is an error on the original drawing for Board F.

Top right hand corner, the input socket is connected to earth!  KF29 Eingang

I have re-drawn it using rotary switches to help me understand it better.



I will probably do the rest over the course of my confinement :D

DaveP
 
gyraf said:
nobody said this was easy  ;D

I agree. I meant that if you’ve been through 25 revisions and still haven’t come up with a satisfactory answer there may not be one. I certainly can’t think of one.
 
I was carrying out a very rough costing on this by adding components from the various schematics.  All was fine until It came to the number of tubes.  The manual says, 9 x ECC81, 4 X ECC83 and 1 x E83F

When I add them from the schematics I get, 7 x ECC81, the rest as above.

I suppose it's inevitable that there will be mistakes on such a complicated circuit.

DaveP
 
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