Oscillator XTAL 701 in NAD C740 xcvr ???

[d0g]

Hello,

Hoping to get some clues with this.

I have a NAD C740 receiver that eventually stopped powering on. I took it to my retailer/repairer who diagnosed it as a faulty oscillator xtal 701.

They claimed that this part was no longer available and therefore could not fix it. This seems a little strange to me given that;

- it is not that old.
- there was no mention of attempts to source an alternative part
- I have not been able to find any oscillators in any NAD schematics that I have found to date.
- an oscillator appears to be very generic to my very limited electronics knowledge ??


Is my repairer telling me porkies to get me to buy a new amp ?

Should alternate parts be available to repair this ?

Cheers

 

[MaxS]

Hello,

Try to get schematics and show them to us.
For me, the cristal is a part of tuner but, I may be wrong.

Max.

 

[poynton]

..................unless it's part of the IR remote ?

 

[d0g]

I haven't been able to find the schematics unfortunately and am reluctant to pay as it is money that I could use for a second opinion...

To my thinking, it seems unlikely that a problem with the tuner or IR functions would prevent it powering up ??

Thanks, I appreciate your comments.

 

[es44]

Well, the Cpu would need a x-tal for sure.

I'm a little bit puzzled here, you mention a, quote: "Oscillator XTAL 701 in NAD C740 xcvr ??? "
To me an xcvr is a transceiver ( transmitter/receiver )
Anyway... I I have a SM for a Nad C730 Receiver, wonder if it's close enough to the C740 to be used for anything ?

If that's the case, then just drop me a mail, then i'll send it to you d0g.

Best regards
Ebbe

 

[d0g]

Thanks Ebbe,

Sorry for the confusion with my abbreviations - it should have read '.. in NAD C740 receiver'.

Please could you send the schematic to me at dmaltern8-safe ' at' yahoo.com.au - That would be awesome.

Cheers

 

[jaycee]

What's printed on the part, and what IC's is it near to?

 

[d0g]

Hi Jaycee,

I have not yet been able to identify the part - this has contributed to my suspicion...

cheers

 

[es44]

Sorry for the confusion with my abbreviations - it should have read '.. in NAD C740 receiver'.
Cheers

No problems It's just me being too picky

Hope You received mail, and that it's close enough.

Best regards
Ebbe

 

[poynton]

Hello,

Hoping to get some clues with this.

I have a NAD C740 receiver that eventually stopped powering on. I took it to my retailer/repairer who diagnosed it as a faulty oscillator xtal 701.

...................................

Surely, a faulty Xtal would not prevent the system from powering on?

Do you mean it's dead or what ?


Andy

 

[d0g]

yeah - it will not power on.

At first it was intermittent (& I lost my saved radio stations) & then it died totally...

 

[d0g]

Ebbe,

Got the mail - many thanks !

 

[poynton]

If it was intermittant, I doubt that a Xtal is the fault !!

Start at the plug and work in, check fuses, switch, power into and out of the transformer, voltage across the main caps and then report back.

Andy

 

[Heinrich Lubbe]

Did you manage to get the c740 fixed? I also have one with a similar problem. Only swithes on with remote. No selection buttons on front panel are working, but inputs can be selected via remote control. I have the schematics and did change the super cap C712 that is responsible for memory. I also get all the voltages as shown on the scematics, but still no luck. Can it be the crystal as well? or would the processor be dead then without any clock frequency?