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GZ37 substitutes

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Hi

I’m looking for an alternative to a GZ37 rectifier tube, which, due to scarcity, has become prohibitively expensive. I use- one per power amp channel- a GZ37 rectified choke input power supply. 500-0- 500 V ac in, 30H choke, 440u cap, ~ 420V out.

The current at idle is about 100mA, but, to allow good dynamic behaviour, and also to accommodate a possible future shunt regulator, etc, I need a minimum continuous current rating of 200 mA minimum (preferably more- the GZ37 is capable of > 300mA with a choke input).

The replacement must be indirectly heated, with a heater requirement of 5 or 6.3 V @ 3A or less.

Unless there’s some ex-Soviet wonder I’ve missed, I’m guess I’m looking for suitable damper diodes. A pair of single rectifiers would be OK, as long as a single heater tap for both is permissible- the typically high heater to cathode voltage ratings of damper diodes would permit this I guess. If I need a pair, a noval configuration might be easier to accommodate, but this isn’t critical.

Any suggestions? Ones that have satisfied users in practice as well as in theory preferred!

Many thanks

Paul N
 
Hi

I’m looking for an alternative to a GZ37 rectifier tube, which, due to scarcity, has become prohibitively expensive. I use- one per power amp channel- a GZ37 rectified choke input power supply. 500-0- 500 V ac in, 30H choke, 440u cap, ~ 420V out.

The current at idle is about 100mA, but, to allow good dynamic behaviour, and also to accommodate a possible future shunt regulator, etc, I need a minimum continuous current rating of 200 mA minimum (preferably more- the GZ37 is capable of > 300mA with a choke input).

The replacement must be indirectly heated, with a heater requirement of 5 or 6.3 V @ 3A or less.

Unless there’s some ex-Soviet wonder I’ve missed, I’m guess I’m looking for suitable damper diodes. A pair of single rectifiers would be OK, as long as a single heater tap for both is permissible- the typically high heater to cathode voltage ratings of damper diodes would permit this I guess. If I need a pair, a noval configuration might be easier to accommodate, but this isn’t critical.

Any suggestions? Ones that have satisfied users in practice as well as in theory preferred!

Many thanks

Paul N


Here is a list I've been using since forever.

Cheers,
Carlos

http://www.fourwater.com/files/fullrect.txt
 
That is a very nice list.

One additional piece of information that would be helpful would be the height of the tube excluding the pins.

In particular, the GZ34/5AR4 (2-53/64", Amperex) is often used in an enclosed chassis where the overall height is critical most 5U4s (4-3/16", RCA)would not fit in my Monarch Receiver.

http://www.mif.pg.gda.pl/homepages/frank/sheets/049/5/5U4GB.pdf


Same for many 5Y3s (4-1/16", 5Y3-G,RCA) However the 5Y3-GT by RCA looks like it might fit as seated height is shown as 2-13/15".

http://www.mif.pg.gda.pl/homepages/frank/sheets/049/5/5Y3G.pdf
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.