Bendix RA-1B

[rosie&jim]

Hi All' Just thought I'd post a few pics of my old Bendix RA-1B receiver which I've owned since the early 60's. I've no reason to think it wont work once I get it powered up but I'm still reviving the PSU capacitors slowly and they seem to be responding well.

[turretslug]

That is a really lovely bit of kit, a "proper" radio. Useful coverage to boot. The thought of what that level of mechanical engineering would cost nowadays is frightening...

[Alan Stepney]

I can remembe rmy father buying one in about 1948.
I still have it and it works well. (Cost £7-10-00)

I have since aquired two others, or rather, one plus the remains of one that I intend to use for spares.

Yours still has the audio transformer in place and the front panel is (almost) original, both of which seem to be unusual.

[rosie&jim]

Originally Posted by Alan Stepney

Yours still has the audio transformer in place and the front panel is (almost) original, both of which seem to be unusual.

Hi Alan, A bit of foolery really the audio transformer was O/C so I cut the can open and fitted an ordinary output tranny for the 6v6 but as a school boy I didn't have the means to solder it back together properly hence the tape around the bottom. I intend to fix that when I have time. The second socket has been removed and the audio control fitted and the local remote switch has gone but the wiring looks almost factory with the bindings still in place so it may have been modified for life on the ground before being disposed of.

Originally Posted by turretslug

That is a really lovely bit of kit, a "proper" radio. Useful coverage to boot. The thought of what that level of mechanical engineering would cost nowadays is frightening...

Thankyou, I'm hoping to get it back to working condition soon I believe it dates from around 1952 and although marked AM (Air Ministry)I think they where fitted mainly to commercial airliners
It's been dry stored on top of the wardrobe for a very long time. Here's a pic of the underside

Dave

[HamishBoxer]

Superb radio,wonder though wether the oil filled caps are prone to failing like AR88 ones?

[rosie&jim]

Originally Posted by HamishBoxer

Superb radio,wonder though wether the oil filled caps are prone to failing like AR88 ones?

Hi' My understanding of those items you refer to is that they are the connectors for the remote control station (like speedometer cables) although I did think they where grease caps for quite a few years. Hence the local/remote switch thats been removed together with the socket for controling the other functions

[Alan Stepney]

I believe that the early ones had a 6F6 for audio output rather than the 6V6 that was used in later versions.
My understanding was that they were used in several WW2 military aircraft, including some Catalinas.

[turretslug]

Think HB was referring to the rectangular metal-case 2- and 3-terminal capacitors featured in the under-chassis view (stamped "Aerovox", colloquially known as "bathtubs"). Any Micamold brand capacitors present are likely to be a liability, too (not to be confused with similar looking genuine mica capacitors which can be very good, Micamolds are paper dielectric types in a brown Bakelite moulding).

[Radio Wrangler]

Dave Penney had one for sale at the G-QRP Rishworth doo a year or so ago. They are rather nicely made and not a set i've ever had or used.

David

[rosie&jim]

Originally Posted by Alan Stepney

I believe that the early ones had a 6F6 for audio output rather than the 6V6 that was used in later versions.

Now then I remember changing the audio bottle for a different one years ago. I think it was part of a mod published in "Shortwave Magazine" around 1961 which I still have in the cupboard. I'll dig it out and have a read when I get back. The output now drives a speaker direct from the phone socket but when I obtained the radio the speaker had a transformer in the speaker case and connected to the "audio" socket on the front panel and "B+" if my memory is telling me the truth.

[rosie&jim]

Originally Posted by turretslug

Think HB was referring to the rectangular metal-case 2- and 3-terminal capacitors featured in the under-chassis view (stamped "Aerovox", colloquially known as "bathtubs").

Ahhh with you now lol. I never gave them a thought as the radio has been reliable after being left unused for quite long periods before so hoping the low humidity of my chosen storage place has not had any effect on them. Shame not to use it really as it did work very well and seemed quite selective on the ham bands but not as convenient as the later solidstate Jap offerings.

[AC/HL]

The transformer would be in the speaker because Avionic equipment is normally designed to feed an audio distribution system. This radio does have a very high output though, enough for a speaker with the right matching.

[rosie&jim]

Hi Bill, I'd agree totally it's got plenty in reserve in the audio dept for driving a speaker even on broadcast stations.
I didn't mention before but the PSU is also valve which I constructed aged 13yrs but I look at it now and think I could do that a lot better. Anyway it'll get a tidy up shortly

[trh01uk]

Originally Posted by Alan Stepney

I can remembe rmy father buying one in about 1948.
I still have it and it works well. (Cost £7-10-00)

Equivalent to £238 in today's money (check values here).

Possibly good value if you remember that it was probably in really good cosmetic condition and fully working when bought.

Richard