SE Electronics, Z5600 A, studio mic with a valve in it for t

[N_Cook]

Someone has been messing about with the 8 pin connector to the power
supply and it is turning freely. Is there an impedance transformer
inside the casing at the top of the mic, its that sort of size of
casing? Any very fine wires inside there to be aware of before
unscrewing it all?
All I can see at the moment is 9 wires in and 8 pins and shroud at the
other end
Hopefully the intermittent problem is that end and not the mic end.

 

[N_Cook]

10 wires in , not 9
Simple Tx inside but no mu-metal cladding, 48R//1120R and no fine wires.
15 seconds of soldering iron on the internal screws holding the
connector section, to break threadlock.
By the time I got inside 2 of the wires had dropped away,unseen, from
the solder points on the connector, wires twisted up like guitar control
failure.
So will have to work out where the blue and white wires would have gone
to. Cannot find a schematic out there

 

[N_Cook]

Anyone any idea what the 555 in the ps is for?
The HT seems to be from 50 Hz mains secondary boosted by diode pump. 555
seems to be associated with the cardio-omni select function.

 

You mena a valve as in a glass state amplifying device commonly known as a tube statesside ? Hmm. Interesting.

Got a camera ? Throw some pictures up of this thing.

Tell you this, this is probably the most fucked up reverse engineering you'll ever do.

If you aren;t all that familoiar with these things there is a writeup here :

http://www.soundonsound.com/sos/feb98/articles/capacitor.html

I didn't read the whole thing, I just wanted somwthing on the dual pattern feature. Apparently they use more than one set of electrodes or whole two mike elements with a reflector. If it has a tube in it, if they went to all that expense then it is proibably the more expensive type, unless of course it is from 1963 or whatever.

One thing is for sure, it might be a bitch but if it has a tube (valve) in it, that it going to likely have three wires coming out of it, not pins. They are easy to break.

On this page :

http://en.wikipedia.org/wiki/Vacuum_tube

Look at the first one on the left in the first picture shows up. That is likely what you'll find in there.

Question : Does this power supply plug in the wall or just ruibn off 48 V power from an XLR connector ? Those little tubes do not pull all that much power. If the whole shebang runs on 48 V, you can probably current limit a power supply to the point where it is impossible to blow anything and then try connecting things. But I would higghlt suggest first being absolutely sur of which pins run the filament. THAT Is the most damagable thing in there and getting that valve/tube will be be very hard and not easy to install either. If you cna find out the ratings of the tube/valve, find out the current draw of the filament and make sure your source will not suppply more. If it runs off 48 V, it might be as easy as a resistor.

Like I said, this is liable to be the most fucked up reverse engineering you ever did.

 

OOPS, a triode will have four wires. Minimum.

 

[Phil Allison]

jurb...@gmail.com wrote:

Question : Does this power supply plug in the wall or just ruibn off 48 V power from an XLR connector ? Those little tubes do not pull all that much power.

** See pic of Z5600A as supplied in case with PSU.

http://medias.audiofanzine.com/images/normal/se-electronics-z5600a-ii-437228.jpg


The PSU supplies several regulated voltages: low voltage DC for the 12AX7 tube heaters and high voltage DC for the plates PLUS a variable DC voltage to polarise the capsule's two diaphragms in various ways to get many different polar patterns. Figure-8, omni, cardioid plus in between settings.

All this comes via an 8 core lead and connectors which also carry the audio output.

While I have not examined this particular mic, I have seen many just like it.

Such mics are very versatile and can be used for almost any sound source in a studio or other INDOOR recording space. They are vulnerable to wind and moisture plus sudden changes in temperature that can cause condensation.

The output level is many times higher than with dynamic mics while self noise is usually very low.


..... Phil

 

[N_Cook]

The 555 must be for the 15 seconds time-delay hold-off before click over
of the relay and the LED flashing for that 15 seconds, so no nasty
oscillator during use proper .
Looks like blue is pin 3 and white is frame ground of the interlinked
pins 4 and 7
192V supply is pin1 , brown, invariant with change of cardio-omni
setting, without the mic pcb connected anyway.
p2 yellow,p5 blak,p6 green, shroud and centre pin not connected to cable .
Next stage to solder back the cable connector into the mic housing and
power up the mic , see if it works , and what changes, if a DC line,
with cardio-omni setting.

 

[N_Cook]

Have to take the Tx and connector apart again. The yellow , heater
supply , wire seems to have a break in it. 6.7V (no load) supply is in
the cable but no heater glow.

 

[N_Cook]

Back working as a mic. Heater 6.4V dc on load, HT 188 to 190V on load.
Blue line varies on pattern type from -0.04V at O, mid of cardio +.011
then next switch steps +27V,54V,82V up to 110V on full bi-direction