Is STV-3H same a STV-3 ?

[qguy]

Is STV-3H same a STV-3 ?

it has "5N" printed on it.

Physically looks the same

 

[Watthour]

They have been referred to as STV3, STV-03H, STV-3H, STV-3, STV-3H-YG, STV-3H0, and probably numerous other names. AFAIK, they are all in reference to the Sanken STV3H-Y diode array.

You might get lucky and find NOS parts somewhere, or make your own. Since you have an example already, protect it like it was gold.

 

[john stumpf]

not trying to horn in but you mentioned the diode 1004 combo to me in the sx9000 thread, how does that work out in actual practice?

 

[Watthour]

If you read that entire thread (seven pages) there is quite a bit of information from practice. Colloquial evidence from practice seems to indicate that the string of UF1004s seems to track fairly well.

 

[john stumpf]

good to know, thank you.

 

[qguy]

Before I buy it, I would like to test it, how do I test this part if it is good?

 

[john stumpf]

like a regular diode. if your using a diode tester the forward will be 2-3 times higher.that looks unused,you find that in manila?

 

[qguy]

Yup, Friend of mine has it, it is NOS

like a regular diode. if your using a diode tester the forward will be 2-3 times higher.that looks unused,you find that in manila?

 

[Hyperion]

Take care of the leads - they can be extremely fragile and break off very easily.

 

[john stumpf]

yeah they can, sort of makes a guy think that NOW is the time to modify with stranded wire.

 

[rcs16]

I glue the braided insulation/wire to the body to act as a strain relief.

 

[LesE]

For info ... I took some V-I measurements to compare an original STV-3H diode against a new STV that is available on eBay. The new ones appear to track quite well with the originals. I've used a few of them and they seem to work fine.

 

[kevzep]

Iv'e used some STV3 diodes from a bay seller in Germany, I am not sure it they make them or if they are NOS, but they look brand new and seem to work well.
In fact today I put one in the SX1250 I am working on.
Lead just fell off one as I was about to fire it up!!
The last tech was pretty rough with this amp, and I suspect this was something to do with some of the issues..

But yeah, those German ebay ones are great, not a bad price too.

 

[aldena007]

As of today (7-15-18) he has only 310 left. He has sold 990 to date so those German diodes are going fast! Get them while you can. Others are selling (or trying to) with an asking price upwards $30.00 a pair. I don't think he has an unlimited supply but his price is around $7 plus shipping so get a few extras.

 

[qguy]

like a regular diode. if your using a diode tester the forward will be 2-3 times higher.that looks unused,you find that in manila?

Mine is reading around 1200 on my DMM on the diode setting

 

[kevzep]

I just measured my new German STV3's and they have a forward voltage of 1.495V.

 

[john stumpf]

thats sounds reasonable to me, when was your meter or mine last been to a calibration lab?

 

[markthefixer]

the forward voltage is dependent upon the temperature (of course!!) but ALSO the test current through it. Different meters have different test currents PLUS the battery condition of the meter at that time has an influence.

The factory pushes through 7 mA at a standard temperature for the rating. And even it is expressed as a range.

 

[pustelniakr]

For the edification of all, please consult the following thread: http://audiokarma.org/forums/index.php?threads/replacing-the-stv-3h-and-4h-diodes.279530/

Enjoy,
Rich P

 

[pustelniakr]

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