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 Racal Antennas Ltd Balun 
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Post Racal Antennas Ltd Balun
I wonder if anyone knows anything about this beast?

I have measured it and it appears to be designed to feed an antenna system using 650Ω, using a 650Ω load it gives a flat reading from below 1400kHz through to beyond 30000kHz with SWR of 1.1:1 or better across the range.

The type number is 905-034 and 1kW power handling. It weighs about 10lbs. I can't see the internal construction because it's potted. It has an "N" type coaxial socket at the bottom.

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Sun Dec 15, 2019 8:02 pm
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 Racal Antennas Ltd Balun 
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Post Re: Racal Antennas Ltd Balun
Well, no one seems to know anything about this little beast so I've done some measurements on it, a 650Ω load gives the best SWR and R+J=0 across the range of 1.4 to above 30mHz.

It was probably used on something like a Rhombic or a terminated folded dipole, I think it would probably work great on the later using open wire line down to ground level, so there would be extremely low loss in the feeder system and the transformer, I call it a transformer rather than a Balun because I think that's what it's intended purpose was.

Any ideas? I would be interested to hear what others think?

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Thu Dec 19, 2019 7:30 pm
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 Racal Antennas Ltd Balun 
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Post Re: Racal Antennas Ltd Balun
Hi, it is a CTS (now SMC owned) built BALUN (unbal > bal) unit for Racal and was for a TF2D folded dipole with a 600 ohm resistor in the back line they produced some years ago. Original # is 50/600/1k/N
Geoff
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Mon Jan 06, 2020 9:06 am
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 Racal Antennas Ltd Balun 
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Joined: Sat Mar 31, 2012 8:11 pm
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Location: Markyate, St Albans, IO91ST
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Post Re: Racal Antennas Ltd Balun
Thanks Geoff, I'd forgotten I had posted this. My guess was right about the terminated folded dipole. I'm not sure what else I could use it for, I'm not really interested in a TF2D they have got quite a high loss on certain frequencies. I'll probably keep it as a curio in the loft.

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Mon Jan 06, 2020 9:48 am
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