Help Please tell me what this is?!

[Nickkip]

Hi Guys

I have this Power Amp I thought it was a Quad 303 as it pairs with a Quad 33 but its NAS has a sticker saying Nottingham Audio Services under it S/N 721

It Says NAS 70 + 70. It looks so much like a Quad 303 just bigger.

Anyone know anything about this amp?

Thanks

Nick

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[struth]

picture might help.. may just have been serviced there

[Nickkip]

Sorry was trying to get them to upload have got 2 up the ones showing the case keep failing to upload

Think it was the 2mb limit on the file size.

Up Now

Some more of the inside.
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[donmarrese]

Could be a 303 clone? Poss DIY job?

Sent from my ONE A2003 using Tapatalk

[Nickkip]

Thank you for you reply.

Been doing some searching online and the case seems to have been brought from the below advert, from a RC 1976 image below

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Image came out small its on page 64 of

https://worldradiohistory.com/UK/Radio-Constructor/70s/RC-1976-05.pdf

[Barry]

I don't think it's a Quad 303 clone.

[Nickkip]

Hi after hours of searching I found this when googling the transistor from another forum..

“
Yes, this is the one. I recall Mainline selling 12, 25, 40 and 70 W amplifier kits in the 70's, which I take it are transistor and diode sets for these amps, but I never bought one”

[walpurgis]

A link would be good.

I googled H&H and WEM images, but I was wrong and obviously didn't find anything.

[Nickkip]

This is the link when I googled the model on the transistor

https://vintage-radio.net/forum/showthread.php?p=495170

[Nickkip]

Im not sure now if its mainline, I have taken it apart and got the boards out.

On the bottom of the boards the is the words NAS 70w 700mw printed on them.

Image below.
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Also any idea were i could get replacement caps for it? tested them one reading 4600uf other 4200uf when should be 3550uf

when testing the board its a 4 channel amp with bridged RR LL so same sound out of both speakers on a single side, so both right will have the same output and both Left.

I was going to repair my B&O 5700 and sell them the crossovers on one went on fire :doh:, got a good set of B&O 5702's that i needed to replace one cap in the crossover as had lost mid, need to do the rest but going do that when i can find some time..

Looking at the Amp do you think its got the power to drive the 4 speakers

photo of my crossover in B&O 5700

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[Firebottle]

Also any idea were i could get replacement caps for it? tested them one reading 4600uf other 4200uf when should be 3550uf

If it reads more than marked then all is good. Large electrolytics have wide tolerance when made.

[Nickkip]

Thank your reply that always good to know!

Tonight I have made a cable to connect the quad 33 to the unknown amp.. well I have to say it does sound good and was only playing it off my phone. Will have to set it up properly at some point..

[snowman_al]

Sorry if this is so obvious it is not mentioned, but do you think NAS stands for Nottingham Audio Services? As it says on the little label.

Nothing comes up on a quick search, but it may spark someones memory perhaps?

[scotty38]

I think he says that in the first post

[snowman_al]

Numpty here, how did I miss that?
Sorry, back under my rock...

[Nickkip]

Thanks for all the help over this, guess it will remain a mystery.