QUAD 303 transistors

[TonyF]

My QUAD 303 amp has lost a transistor - Tr105 PNP driver
38496 (=BC143,2N4037). What is a modern substitute ? One Web page suggests BC461. Any other ideas ?
Cheers Tony

[Graham Maynard]

Hi Tony,

Have you tried e-mailing Quad, they are well known for their excellent after sales back-up.

From experience I would be very wary about subbing a transistor in a Quad amp if you want it to sound the same as they intended.
I'm sure they'll send you the correct part via a credit card order, even if you are not in the trade.

Is that driver the only faulty part though ?

Cheers ........ Graham.

[paddy]

Quad support is worldclass you'll have the parts immediately if you just ask

[TonyF]

Thanks Graham and Paddy. Got an automated reply from QUAD saying that the Service Manager was on holiday for 2 weeks ......

But I have now located a source of BC143, but indeed this may not be the only fault.
Cheers Tony

[paddy]

What are the chances! I've had no problems in the past. If you call them they can probably refer you to someone internally.

My towers transistor selector is 150 miles away at the moment so I can't help you with a replacement, if you are replaceing tr105 I would look at replacing tr106 also with a compliment to your chosen transistor .. if your other channel is still ok it should be easy to check the suitability of the replacement.

Please do look at this site though it seems they might know what they're talking about -

http://www.geocities.com/ResearchTri...dequitran.html

Both the BC441 and BC461 are available from

www.farnell.com (click the aussie flag edit:sorry kiwi flag)

Best of luck,

Paddy

[TonyF]

I finally have a reply from the Service Manager who had been on leave . He gave me the price for a replacement, with some comments about credit card usage. I replied saying I had been seeking info about a current replacement.
He has now replied saying that all they do is supply.
I rather think service standards have slipped ....
Cheers Tony

[paddy]

That's a pity, they were so helpful in the past. The again he is a manager, most managers I've worked under didn't know their **** from their elbow when it came to things technical.

How much are they charging? Are they supplying the original transistor or an equivalent?

Good Luck,

Paddy

[TonyF]

Hello Paddy. How about 1.14 GBP +VAT + postage !!!!
I am really surprised that a request for info on a modern replace would yield such a response. I have asked him to say what the transistor is/

I may not get a reply ..
Cheers Tony

[UrSv]

Originally posted by TonyF
Hello Paddy. How about 1.14 GBP +VAT + postage !!!!
I am really surprised that a request for info on a modern replace would yield such a response. I have asked him to say what the transistor is/

I may not get a reply ..
Cheers Tony

Seems very reasonable and would have gone for it without hesitation.

[Graham Maynard]

TonyF

I would buy them. Sounds like excellent service to me.

Quad stocked RCA, and the characteristics matched their design for stability and sound etc.

There were two versions of your amplifier - relating to slightly different bias setting arrangements. Serial no. is relevent for that.

You would probably pay near that for quality substitutes anyway, and you still won't be sure they match.

Cheers ........... Graham.