Any Racal RA-17 Users in the House?

[Todd, KA1KAQ]

Yes Frank, I know: the older tube gear is awful! 

Despite being warned, this past weekend I took in a nice RA-17C  as partial trade for the Alpha PA-77. It included the Sideband adapter and Low Frequency converter. Other than some yellowing of the panels and mild oxidation on the aluminum chassis, it looks to have been well taken care of. The previous owner mentioned that he got it from a friend who worked in Bell Labs, where the receiver spent its early life.

I'm curious to hear firsthand experiences, particularly with the converters in line. I had a RA-17UC some years back but sold it to pay my property taxes. The rolling film strip dial is a hoot, and the tiny speaker makes decent audio, despite being very low power. They are a bear to service due to their cast aluminum sub-chassis construction, that much I do remember.

I bet Johnny Novice had one of these at some point. 

[WQ9E]

Hi Todd,

I picked up one of these last year at the Princeton, IL hamfest and went through it several months ago.  The VFO in mine had an attempted repair from a previous user and it was mechanically damaged to the point I had to find a replacement unit.  I didn't get the fancy sideband adapter with mine so lucky you!  There was a homebrew product detector added but since it wasn't neatly done I removed it and restored the radio to stock.

It is a fun receiver and the "clickless" bandswitching using the broadband front-end position is pretty neat.  Mine came with a pretty complete manual with A LOT of updates issued by Racal over the years.  It seems the power supply section was the subject of a lot of changes with the early receivers including parts value changes and fuse additions.

I have my receiver rack mounted and it gets a fair amount of usage though it isn't connected with a transmitter at the present time.  I picked up another Wadley loop receiver at a hamfest yesterday, the Yaesu FRG-7.  Cute little Yaesu but the IF selectivity is not so great.  Of the three Wadley loop receivers here the Racal RA-17 is definitely in first place, the Yaesu FRG-7 in second, and the Radio Shack DX-302 scoring points for style but dead last for performance.

I will be interested in hearing how your low frequency converter works out.

73, Rodge WQ9E

[ve6pg]

..TODD...TIM HR...KEN, VE3MAW HAS ONE...HE IS USUALLY ON, SAT/SUN MORNS, AT ABT 8:30-ON..SOMETIMES 4-6PM DURING THE WEEK, AND WEEKENDS...3725...SEE YA...sk..

[w3jn]

One of the few I've never had, Todd.  I do have a Wadley loop Racal - the 6217 which looks like a submini R-390.  Solid state and an absolutely abominable front end (even worse than the second runner-up, the 51S-1), but very cool otherwise with the mechanical digital counter.

[Todd, KA1KAQ]

Huh. Could've sworn t'was you. Did Steve have one?

Apparently they were Racal's answer to the R-388 originally, probably the R-390 later. Only problem is, unlike the R-390 with removable modules, you have to disassemble big chunks of the receiver to get access to the underside of some modules. A major pita to service, but should be good for decades once it's done up right. Triple conversion, stable as a rock, and an interesting preselector approach to bandswitching. Takes some getting used to.

And as you've no doubt notice, Rodger - it tunes SSB pretty easily without the adapter. I've never used one before, so that in itself will be interesting.

[WQ9E]

Hi Todd,

Yep, I think it works fine on SSB without an adapter.  I have in mounted in a rack along with an SP-600 and an R-390A.  The R-390A is feeding an Eldico SSB adapter but I have used the Racal paired with a CE-20 and it worked fine on SSB.  Properly set up, the tuning feel on the Racal is excellent though I am concerned that sooner or later the 35 mm film strip dial is going to crack.

Rodger WQ9E

[WA1GFZ]

R17 film shows up on ebay fairly regular.
John, the 6217 is beautiful inside but you set me straight a while ago so never bought one. I wonder if it is worth hot rodding. I ran into an old Racal guy who said they designed their high dynamic range mixer first used in the 6772 during a meal on scrap paper. The early one had an IP3 looked close to plus 40 dBM. They backed off on the LO later. I suspect the roofing filter ran out of steam first. Even the later units roofing filters run out of steam at plus 30 dBM IP3.
Networks international builds filters for most premium mil receivers and specs are pretty much the same except for different bandwidths.

[Todd, KA1KAQ]

Rodger, there is or was a fellow in either NJ of on L.I. NY who specialized in the tube type Racal gear. Think his name is Gary Weingart or something along those lines. He had mucho spares, including the film strip dials and most modules and parts. Somewhere I have his information. Finding it is another matter.

My fear would be less the strip breaking and more how to 'reload' a new one with proper spring tension on the rollers and so on. Looks like a real project to replace. But it beats out the SP-600 in my book for ease and feel of tuning, and really hears the weak stuff with little background noise.

[WA1GFZ]

Gary Wingerd is a great guy I've done a lot of RA6830 stuff with him.
He bought a pile of stuff from Racal when they stopped making HF receivers.

[Mike/W8BAC]

Todd,

Is your receiver a US or European version? I lucked into a US model with US tubes. I have the LF converter but no sideband adapter. I saw the holy grail go by on eBay recently. The dual diversity adapter. It went for a small fortune.

The receiver is very sensitive and quiet. After all the years in use the calibration is still very good. My top and bottom covers are gone unfortunately. Have fun!

Mike

[w3jn]

R17 film shows up on ebay fairly regular.
John, the 6217 is beautiful inside but you set me straight a while ago so never bought one. I wonder if it is worth hot rodding. I ran into an old Racal guy who said they designed their high dynamic range mixer first used in the 6772 during a meal on scrap paper. The early one had an IP3 looked close to plus 40 dBM. They backed off on the LO later. I suspect the roofing filter ran out of steam first. Even the later units roofing filters run out of steam at plus 30 dBM IP3.
Networks international builds filters for most premium mil receivers and specs are pretty much the same except for different bandwidths.

It's more of a matter of using germanium transistors in the RF amp and mixer.

[WA1GFZ]

Wow sounds pretty old. might make a nice preselector though. loop must have real old logic. Still a work of art inside.

[Todd, KA1KAQ]

Is your receiver a US or European version? I lucked into a US model with US tubes. I have the LF converter but no sideband adapter. I saw the holy grail go by on eBay recently. The dual diversity adapter. It went for a small fortune.

It's the US model, Mike: RA-17C. Think it was made in Maryland, maybe Virginia. Haven't hooked up either of the adapters yet, need to find a decent cabinet first with at least 17.5" of rack space. Think I may have tossed all of my old 75 ohm BNC jumpers, too.

One of the fellows in UK has or had a nice Racal page up years back. I used to visit it and drool. It's amazing how many accessories and other trinkets they made for these things. I think he even had some matching transmitting gear. I figure this stuff is to them what the R-390 family of receivers is to us.

In top form, they are one of the best receivers out there. Stable, quiet, sensitive. Getting it into top form is the interesting part.

[ve6pg]

...TODD...AL, VE3AJM HAS A 9FT STACK OF THEM, USEFUL FER PARTS...TIM...SK..

[w3jn]

Wow sounds pretty old. might make a nice preselector though. loop must have real old logic. Still a work of art inside.

No logic at all, Frank, it's a Wadley loop.  Essentially a solid state version of a RA-17.

[WQ9E]

Hi Todd,

Reloading the film strip is not a problem, I had to do this when I replaced the damaged tuning unit in my RA-17.  By the way, mine is an odd hybrid that is mostly American but it has the English style audio stage.  I can't complain, it looks nice and it only cost me $35 for the receiver and I found the replacement VFO for $25.

I remember the old beginner magazine, Ham Radio Horizons, had an article on the Wadley loop receivers and covered the RA-17 in addition to a solid state portable using the same technique.  Going on memory but I think it was a Barlow XCR-30.  It would be fun to find one to play with.

Back to fun with my newly restored Viking 500, the only remaining issue is the swinging choke buzzes and it causes the power supply case top to sing along with it.  I can quiet it by resting a foot on the case but I think I am going to find a better solution than keeping a foot propped on the 2000 volt power supply while holding onto the mic with my hand.  I know it is all grounded but it still doesn't seem like such a great idea!

73, Rodger WQ9E

[WA1GFZ]

so John, Is it harmonics of 1 MHz. mixed with a PTO? I wonder if that is cleaner than a synthesizer.
Oh well life is short i will stick with HPSDR and later sit on the beach.

[w3jn]

Exactly, Frank, the harmonics are mixed and upconverted, going thru a 45 MHz or so L/C filter then converted back down.  Essentially what's happening is you're picking off the correct 1 MHz harmonic for the first conversion.  It all depends upon a clean 1 MHz oscillator because the harmonics get dirtier and dirtier as you go up.  My 6217 is pretty quiet.

[WA1GFZ]

Clean 1 MHz would be easy. Then it is just a matter of filtering out the right harmonic. I bet the present hardware would do that. So maybe this cool looking radio could be turned into something cool. What kind of filters does it have for various modes and are they a common IF like 455 KHz or 1.4 MHz.
Heck one could add a divide by N control off the MHz switch and divide a 100 MHz or even higher oscillator down to improve phase noise. Ah......maybe this could be a cool radio. HMMM a 600 MHz SAW VCXO an the main oscillator locked to GPS.
Rip out all those old transistors and fill it full of 2N5109s.
The machanical design looks like a swiss watch.

[w3jn]

Filters are 1.6 MHz.  Nothing wrong with the oscillators, it's the front end and prolly the first mixer that's absolute junk.  AGC action is nice and smooth and decent audio response out of the line level output.  I had a set of filters from one of these that I used in my HB receiver.

[WA1GFZ]

Gee, that sounds easy to fix. Does it have a tracking preselector?
I have found the present limits of performance in the hot rod RX world are phase noise and roofing filter power limit. Mixers are easy now and amplifiers are also no big deal.
The 6712 should be as clean as an R390 but in a smaller package.

[Todd, KA1KAQ]

I remember the old beginner magazine, Ham Radio Horizons, had an article on the Wadley loop receivers and covered the RA-17 in addition to a solid state portable using the same technique.  Going on memory but I think it was a Barlow XCR-30.  It would be fun to find one to play with.

Think you're right on the name/model, Rodger. I've seen pictures of them, they look like the last gasp Zenith solid state sets having a bad hair day. They turn up in the UK and Oz fairly often.

Update: last night I found a BNC jumper cable and hooked up the SSB adapter. Turned it on, let it warm up, tuned the receiver to a signal with BFO off. Switched off the speaker in the receiver, switched on the one in the RA63 adapter and there was the signal, right on the money. I adjusted the fine tuning a bit, but it really wasn't needed.

So I can say that using the SSB adapter is a breeze, it works great. Plug it in, plug in the jumper from one of the 100kcs I.F. outputs on the receiver to the adapter, you're in business.

Also checked the tag a little closer. It's a 17C-3. Fredericksburg, MD IIRC.

Here's the link for the Racal site I was referring to yesterday. John, I think the nixie version of your receiver is right in the center/top photo, sitting atop a RA63 adapter:

http://www.recelectronics.demon.co.uk/

[Les Locklear]

Yes Frank, I know: the older tube gear is awful! 

Despite being warned, this past weekend I took in a nice RA-17C  as partial trade for the Alpha PA-77. It included the Sideband adapter and Low Frequency converter. Other than some yellowing of the panels and mild oxidation on the aluminum chassis, it looks to have been well taken care of. The previous owner mentioned that he got it from a friend who worked in Bell Labs, where the receiver spent its early life.

I'm curious to hear firsthand experiences, particularly with the converters in line. I had a RA-17UC some years back but sold it to pay my property taxes. The rolling film strip dial is a hoot, and the tiny speaker makes decent audio, despite being very low power. They are a bear to service due to their cast aluminum sub-chassis construction, that much I do remember.

I bet Johnny Novice had one of these at some point. 

I had a RA-17C.12 that was used by the FCC Monitoring Station in Michigan several years ago. They are a fine receiver and very stable One can copy ssb w/o an adapter, but those are great accessories to have.