Question about FET 2SK117 in old stereo receiver

[Zeljko]

I have an old stereo receiver which has two FETs in preamplifier stage, they are 2SK117 and probably they doesn't work. I bought new 2sk117, but what I wish to know; original FET was 2sk117 GR and I have new 2SK117Y. The different between those two FETs is in IDSS,
Y has 1.2~3.0 mA, GR has 2.6~6.5 mA, BL has 6~14 mA.

So my question is, can I use this 2SK117 Y instead 2SK117 GR (Service manual recommended to use 2SK117 GR or BL). What will be if I use that 2SK117Y ?

Regards!

[Zen Mod]

Originally posted by Zeljko
I have an old stereo receiver which has two FETs in preamplifier stage, they are 2SK117 and probably they doesn't work. I bought new 2sk117, but what I wish to know; original FET was 2sk117 GR and I have new 2SK117Y. The different between those two FETs is in IDSS,
Y has 1.2~3.0 mA, GR has 2.6~6.5 mA, BL has 6~14 mA.

So my question is, can I use this 2SK117 Y instead 2SK117 GR (Service manual recommended to use 2SK117 GR or BL). What will be if I use that 2SK117Y ?

Regards!

1. mebbe it will work ok
2. mebbe it will sound sound distorted
3. mebbe it will go puf


just try them

[EUVL]

I would also recommend you to use GR or BL. Using Y will probably place the FETs in positive-bias (if e.g. driven by a CCS) -- bad idea.

But it will make life much easier if you have the schematics.


Patrick

[Zeljko]

Originally posted by EUVL

But it will make life much easier if you have the schematics.


Patrick

OK, here it is...

Regards!

[EchoWars]

Are you sure the old ones are bad? They aren't known for failure...

One part on your schematic IS known for high-failure...D1 and D2, the VD1212 diodes. They can be replaced with a simple series pair of 1N4148 diodes. If you're having problems with that part of the preamp, get rid of the VD1212 diodes first. Every time I find them, I pull them out.

...looks like a Sansui something-or-other...

[Zeljko]

Originally posted by EchoWars
Are you sure the old ones are bad? They aren't known for failure...

I am thinking that someone has connected DVD Player or CD player on that Phono input…

Originally posted by EchoWars
One part on your schematic IS known for high-failure...D1 and D2, the VD1212 diodes. They can be replaced with a simple series pair of 1N4148 diodes. If you're having problems with that part of the preamp, get rid of the VD1212 diodes first. Every time I find them, I pull them out.

I checked those two diodes by digital multimeter, and they are good.

Originally posted by EchoWars
...looks like a Sansui something-or-other...

Yes, it is Sansui receiver
What's new on AK ?

Regards!

[Netlist]

Originally posted by Zeljko
Yes, it is Sansui receiver

Type number?

/Hugo

[Zeljko]

Originally posted by Netlist


Type number?

G8000

Regards!

[EchoWars]

Originally posted by Zeljko
I checked those two diodes by digital multimeter, and they are good.

Well, they nearly always check out fine with the tiny current that a meter puts through them.

I'm not sure that feeding the phono input with a CD player would kill it. I don't think it would have sounded very good, but it really should not blow up the phono stage.

Is the phono dead? Or just sound bad?

[Zeljko]

Originally posted by EchoWars
Well, they nearly always check out fine with the tiny current that a meter puts through them.

On what better way I can check this diode?

Originally posted by EchoWars
I'm not sure that feeding the phono input with a CD player would kill it. I don't think it would have sounded very good, but it really should not blow up the phono stage.

Is the phono dead? Or just sound bad?

I got this receiver in very bad condition, and both channels on this phono stage are dead. I bought in local store some 2SK117 but not BR or GR, just only Y (as I written before different is only in IDSS). So, what will be if I replace that original with this Y FETs? Can it work for a long time, if it will work?

Regards!