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Trickie_Dickie
23-11-2010, 16:15
Hi everyone. Newbie here goes by the name of Richard to my friends.
Anyway, I'm here looking for advice / infomation.
Years ago, my uncle in Bristol (builds turntables) rebuild some old BBC amps and got me to sort out a couple of wiring mistakes. Well, one look at these amps and I was in love. Couldn't afford to buy them and have looking ever since to find a couple to rebuild with his help.
I've been told they are as rare as hen's teeth now so I thought why not build my own from scratch. I believe they're based upon the Mullard 5-20 and I have sourced most of the components except the chassis. My cousin (keeping it in the family) can make anything out of metal ( he says) if I can give him some drawings. This what I am asking for now. Any info or pictures that I can use to make these amps really look the part.
Can any of you help, please?
Lodgesound
23-11-2010, 16:20
Hi there;

The amplifier you are referring to is I believe called an AM 8/4 - it had 2 large Mullard output valves in it if memory serves and was enclosed in a Hammerite painted cage affair I think.

I only saw one once in my time at the BBC - they were rare then - many many were scrapped - they were at one time the standard monitoring amplifier for driving the speakers in VT cubicles and monitoring rooms.
The Grand Wazoo
23-11-2010, 16:54
Hi Richard,
Welcome to the Art of Sound!

There's a big spreadsheet that you can download HERE (http://www.google.co.uk/url?sa=t&source=web&cd=7&ved=0CD8QFjAG&url=http%3A%2F%2Fwww.bbceng.info%2FDesigns%2Fdesig ns_EDI_sheets%2FCode_Record2.xls&ei=mevrTJCYLoexhQfms8HNDA&usg=AFQjCNFhtMGs1avG2ZDC7JrwG6Pr9YzGUw). It lists a huge amount of the amps & speakers that the BBC used and each piece is listed by it's coding number. For some of the entries on the spreadsheet there are links to scans of the Engineering Design Information sheets.
Your amps may (or may not) be on there. Hope this helps.

Cheers
Trickie_Dickie
25-11-2010, 06:55
Many thanks for the input, chaps. :interesting:
A photo and/or drawings would be extremely usefull. Anyone?

Or a blank chassis or two? :lol:
Trickie_Dickie
10-12-2010, 08:23
Did I mention money? Can't afford much, though. Any condition.
Trickie_Dickie
08-01-2011, 23:49
Well, I've finally got the correct number. Its BBC AM8/6 that I'm looking for. 2 in any condition.
Trickie_Dickie
09-01-2011, 18:13
Well, I've finally got the correct number. Its BBC AM8/6 that I'm looking for. 2 in any condition.

BTW, how do I put a picture on here from my computer?
Reid Malenfant
09-01-2011, 18:58
BTW, how do I put a picture on here from my computer?
Click me to find out ;) (http://theartofsound.net/forum/showthread.php?t=2)

All the best.
Trickie_Dickie
10-01-2011, 10:39
Click me to find out ;) (http://theartofsound.net/forum/showthread.php?t=2)

All the best.

Many thanks. I see now where I was going wrong.
Trickie_Dickie
11-01-2011, 08:00
Now, a circuit diagram would be very useful. :scratch: