Servicing a zx500,what should be done?

[jamie6662]

I recently recieved a zx500 and zx 450 i have not powered on yet and am taking them for service first.The guy whos doing it does home audio in which they hand build amps,crossovers and speakers for high end systems and have been doing since 1968 so know there stuff,but they have asked me to specify whats to be done and any wiring diagram info?
So if somebody can point in right direction.
I so far know about the cap replacement via Erics tutorial .
How about dc offset/ output ?anything else that needs checking?updating or problems to look out for?
I also need to change the fan on zx500 v1 does anyone know what spec it should be replaced with?
Iam learning alot from the forum but not confident enough yet to risk killing my amps

[zeropoint0.5]

it's a good thing you didn't power them up yet.........

replace certainly the input caps, yes dc offset and bias have to set back good(very important)......

for the fan's, the panaflo model is no longer available.......i'll see for a possible replacement......

i would replace them in both amps........

for the rest if nothing is damaged, you don't have to replace it......

[jamie6662]

Ok, I'm not using the 450 yet was thinking I may use the v2 fan out of that but don't really want to do that as its in very nice original condition so would be better if I can find something new. I have looked around but not found voltage/airflow settings for fan yet so if you know that would be great

[zeropoint0.5]

Ok, I'm not using the 450 yet was thinking I may use the v2 fan out of that but don't really want to do that as its in very nice original condition so would be better if I can find something new. I have looked around but not found voltage/airflow settings for fan yet so if you know that would be great

So the 450 is v2 and the 500 is v1 ????

please don't use a V2 fan in the V1 amp or you have to replace one resistor from 91 ohm by a 51 ohm/2W model(V2)

i should have to check on newark/mouser/digikey for some fans..........

the V2 fan moves more air but is way louder then the V1 fan........

[zeropoint0.5]

here's the replacement fan for the zx V1 amp

http://www.newark.com/nmb-technologies/ ... dp/41J3276

and here's the replacement fan for the zx V2 amp

http://www.newark.com/adda/ad0812hb-d71 ... dp/45T0214

good luck........ if you order them it will probably be without a connector.............

[jamie6662]

Awsome thanks for that zeropoint.Yeah i should have said zx450 v2 and zx500 v1 i do have a mint zx350 v1 i could take fan out of but seems though that replacement is cheap and amp is under false floor fan noise not such an issue

[zeropoint0.5]

Awsome thanks for that zeropoint.Yeah i should have said zx450 v2 and zx500 v1 i do have a mint zx350 v1 i could take fan out of but seems though that replacement is cheap and amp is under false floor fan noise not such an issue

To stay easy, don't switch v1 & v2 amp cause you have to replace a resistor on the vertikal daughter board.....

Just put in a new one from the links and you'll be fine....