BBC transformers

[bram]

LL probably just means line/line or something. They came with a load of 52 BBC cards called AM5/17 and what seems to be 4 mixing/summing panels to insert the cards (code SP23528.5.1A1 ). Anyway I bought them thinking it were audix cards in a 12:1 summing configuration but in reality it seems a lot more complicated. I'll post pictures when I get my camera back.
Regards,
Bram

 

[rodabod]

Bram, if you wait a while, I can probably get you some information on those transformers. I'll be back in London at the weekend.

Roddy

 

[bram]

Any news on this transformer, or the amp cards? the am5/17 cards contain a bc109, bcy71 and 2N2904a transistor. They also have a fuse each (oh where is my camera?)

bram

 

[rodabod]

I'm back in work today. I'll see if I can go down to the projects lab and borrow their transformer data sheets.

Roddy

 

[rodabod]

[quote author="bram"]
"LL/88 asc" is apparently the type.
Anyone knows about these, turns ratio, uses, etc.?
[/quote]

LL88ASC:

Ratio = 1:1
Primary Inductance = 10.6 Henries
Primary Resistance = 40 Ohms
Secondary Resistance = 65 Ohms

 

[rodabod]

[quote author="bram"]
- "LL/81 msc": small (25mm dia), only 4 leads come out, instead of the 5 of the others.[/quote]

LL/81:

Ratio = 1:1
Primary Inductance = 49 Henries
Primary Reistance = 316 Ohms
Secondary Resistance = 405 Ohms

 

[bram]

Thanks a lot! :thumb: :guinness: :guinness:

bram

 

[Kid Squid]

Rod,
Can you get any 'winding specs' ? for any of the BBC iron ??

I'll pass them on to my mate, and see if he can whip a few out...

Just a thought,
Steve :thumb:

 

[rodabod]

[quote author="Kid Squid"]Rod,
Can you get any 'winding specs' ? for any of the BBC iron ??[/quote]

Hi Steve,

By "winding specs" do you mean the type of construction, etc? There doesn't seem to be any of this in my data sheets.

I think it would often have been Brian Sowter or his father who would have worked with the R&D engineers to come up with a final design. Some of the models are very expensive to make (eg. up to £70 in the 70's/80's from Sowter as an internal price).

 

[Kid Squid]

No worries Rod,
Just as I thought mate :wink:

By "winding specs" do you mean the type of construction, etc? There doesn't seem to be any of this in my data sheets.

I think it would often have been Brian Sowter or his father who would have worked with the R&D engineers to come up with a final design. Some of the models are very expensive to make (eg. up to £70 in the 70's/80's from Sowter as an internal price).

Laters
Steve :thumb:

 

[rodabod]

[quote author="Kid Squid"]No worries Rod,
Just as I thought mate :wink: [/quote]

But there is always the alternative of CJ'ing some of them...

 

[Kid Squid]

But there is always the alternative of CJ'ing some of them...

indeed.
Have you spoke to him about it ? just curious.....

Steve :thumb:

 

[rodabod]

[quote author="Kid Squid"]
Have you spoke to him about it ? just curious.....[/quote]

No, although I have asked him aboput particular models. I'd need to acquire more of them before I'd be able to send some to the slaughterhouse.

 

[Kid Squid]

'nuff said, Old bean
:thumb:

 

[T-Dogg]

Hi,

I have the following transformers out of a Rotronics-built BBC 4-track editing system (lots of canford parts inside...):

LL/76 MSC
LG/65 MSC

This thread is the only reference I've found to these parts outside of a broken Canford website link. Thanks Rodabod, for shedding some light :idea: on the LL/76... Gotta ask -- any chance you'd have specs on the LG/65 as well? Its of the same casing and build as the '76 with identical Red/Green/Blue/Yellow wiring...

Any info appreciated

 

[zebra50]

I found this in my notes - must have scoped it out sometime.

I used a couple as G9 o/p transformers. They were quite good.

 

[rodabod]

[quote author="T-Dogg"]
LL/76 MSC
LG/65 MSC
[/quote]

LG65:

4:1 ratio

84H primary, 650R primary, 160R secondary.

LL76:

1:1 ratio

8.6H primary, 60R primary, 60R secondary.

 

[T-Dogg]

Thank you both very much!

 

[s2udio]

Yup i know this is necromancy but ...
Don't know if Rod is still around ..?
Long shot but
Anyways,,, got some BBC Tx's
# LG/63A
Rod if your still out there any info ? or anyone else versed in bbc hardware.
Thanks.........in anticipation

 

[rodabod]

Stand by. Will have a look when I have some free time.