EMI RD4/4 reel to reel tape recorder BBC mod from the EMI BTR-2

The RD4/4 machine is an in-house design from the BBC, the recorder was a BTR-2 before all the mono valve electronics were removed and replaced with transistor electronics and addittional tape tension and reel size selection controls added.

Category:

Education

Tags:

• reel to reel
• tape recorder
• vintagerecorder
• EMI recorder
• Early BBC
• BBC equipement
• BTR-2
• RD4/4

[Germannio]

Also I'm some intrigued about the odd profile of recording head and inner reproduce head shieldings that shows a clear bump in the front. Could this one be due to get a better stray field rejection without the need of a front hinged Mu-metal screen like the one used in reproduce head of Revox machines?

Thanks in advance.

[Seblington]

Not sure, the machines were built in 1952 so its more than likely over engineering

[Germannio]

What a superb machines!!!

I must admit that EMI's were (till now) a bit unknow machines for me. I know Studer-Revox recorders far better, but I also must admit that EMI RD series must be great studio stationary use "magnetophons".

The first thing that surprised me when I watched pictures of these machines was the huge size of head shieldings, especialy the outer one of the reproduce head.

I have some high-res pics of erase heads and this seems to fit two elements into the shielding. I'm true?

[Seblington]

Yes, onthe replay only the record has one shield

[Germannio]

Thanks for your replies.

Obviously EMI engineers didn't economize Mu-metal to make such a huge shields. I always though that Studer-Revox shields were a bit oversized, but after have seen these ones it's clear that EMI gained the upper hand to Studer ;-)))

It's obvious that designers did a very well engineering job 60 years ago and they spared no effort to get a true sturdy and reliable studio machine that could rival with German AEG Magnetophon or American Ampex 300 and later 350 recorders.

[viceadmiraal61]

i like your video ,but please use next time a plop filter on the mic..it,s better

for my small loudspeaker....

[btown2011]

im waiting to see the next unit you have bought.

[TVperson1]

Going from mono to stereo? That's a heavy mod, but I suppose if was cheaper than a stereo machine.

[btown2011]

i find sewing machine oil works, its very light oil.

[btown2011]

not supprised, you dont have any ampex's though do you? i got a 354 the only tube stereo one they make, it uses the 350 transport.