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THE AM BULLETIN BOARD => QSO => Topic started by: k4kyv on June 17, 2005, 11:34:33 PM



Title: 75A-4 with a steering wheel
Post by: k4kyv on June 17, 2005, 11:34:33 PM
(http://www.qrz.com/uploads/post-7-50509-75a4.jpeg)


Title: 75A-4 with a steering wheel
Post by: WV Hoopie on June 17, 2005, 11:52:53 PM
Darn glad the newer models have power steering,


Title: 75A-4 with a steering wheel
Post by: wa2zdy on June 18, 2005, 12:17:14 PM
Nice receiver.  It looks familiar . . .


Title: 75A-4 with a steering wheel
Post by: W3SLK on June 18, 2005, 02:00:35 PM
That's the Art Collins Fine Tuning Module for the 75A4. I would presume you will see it prominately displayed at the CCA Museum in Johnstown, PA


Title: 75A-4 with a steering wheel
Post by: w3jn on June 18, 2005, 06:00:45 PM
Oh my God oh my God Oh my God someone actually had the NERVE to modify a Collins receiver?  

Looks like the steering wheel off my lawn tractor.  The lawn tractor is about as good a receiver as a 75A-4 too.


Title: 75A-4 with a steering wheel
Post by: Vortex Joe - N3IBX on June 18, 2005, 08:19:50 PM
What'll they think of next? A 75A-4 that'll tune in to W2VJZ and cut your lawn at the same time. Makes me wanna go out and mown the lawn all day listening to good oldfashioned preachin 'bout Jesus,Jefferson, and Jersey!


Title: 75A-4 with a steering wheel
Post by: Ed - N3LHB on June 18, 2005, 10:13:10 PM
It's amazing what some hams will do to not have to pay the outrageous prices that 4 to 1 reduction knobs are commanding these days....

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5769356689


Title: 75A-4 with a steering wheel
Post by: wavebourn on June 19, 2005, 01:56:51 AM
I saw vintage Zenyth receivers with such steering wheels.


Title: 75A-4 with a steering wheel
Post by: k4kyv on June 19, 2005, 02:55:20 AM
Quote from: Ed - N3LHB
It's amazing what some hams will do to not have to pay the outrageous prices that 4 to 1 reduction knobs are commanding these days....

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5769356689


Wow.  I paid $35 for mine back in the early 80's from the old Ham Trader Yellow Sheets.  Box had never been opened.  Everything, even the tiny washers and set screws, was sealed in its own miniature manilla envelope with the collins part number stamped on the outside.

I suspect collectors today would not be interested in opening the box of a virgin unit, but would put it on the shelf as a collector item with no intent to ever install it in a receiver.

I paid only $100 for the receiver, with all 3 filters included.  Someone had busted the spinner knob and then ruined the vernier mechanism trying to remove it, using an allen wrench instead of the spline tool required.


Title: steering wheel
Post by: km1r on June 19, 2005, 06:09:56 PM
no no no, thats the very rare

            RAPID QSY CONTEST MODEL 'A4

zoooooooooom !

73,

Mike KM1R


Title: 75A-4 with a steering wheel
Post by: nq5t on June 19, 2005, 11:18:48 PM
Quote from: k4kyv


Wow.  I paid $35 for mine back in the early 80's from the old Ham Trader Yellow Sheets.  Box had never been opened.  Everything, even the tiny washers and set screws, was sealed in its own miniature manilla envelope with the collins part number stamped on the outside.

I paid only $100 for the receiver, with all 3 filters included.  


That may be ... But that was then, and this is now :-)  

Still $600 for a 4:1 thingy is ridiculous.  Someone made a run of repro 4:1 units that were resonably priced (reasonable is a relative term, of course) not too long ago.  Under $200, as I recall.

For that amount of money I could learn to tune very s-l-o-o-o-w-ly without the 4:1 :-)


Title: Re: steering wheel
Post by: wa2zdy on June 20, 2005, 06:32:02 AM
Quote from: km1r
no no no, thats the very rare

            RAPID QSY CONTEST MODEL 'A4

zoooooooooom !

 



Ahhhhh thnks Mike.  I've been wondering, and now thanks to you it all make sense!


Title: 75A-4 with a steering wheel
Post by: k4kyv on June 20, 2005, 11:52:42 AM
Quote from: nq5t
$600 for a 4:1 thingy is ridiculous.  Someone made a run of repro 4:1 units that were resonably priced (reasonable is a relative term, of course) not too long ago.  Under $200, as I recall.

For that amount of money I could learn to tune very s-l-o-o-o-w-ly without the 4:1 :-)


Now that that sale on e-pay has occurred, everyone will want at least $600 for a NIB spinner knob and vernier mechanism.  Used units will go for less, but if in good shape, not much less.

Considering the current, going price of the receiver, $200 is not bad.  That's what a repro 6-kc AM mechanical filter, that works identically to the original, is sold for in the Electric Radio ad.

Lacking a stock or repro vernier mechanism, a substitute could be fabricated using a National Velvet Vernier dial, similar to the ones on the BC-375 tuning unit.  They were sold by National as a type "AM" dial.  (I would avoid dismantling an original pre-WW2 type A round bakelite dial - they are too valuable).

Without drilling any holes in the A4 cabinet, a bracket could be fabricated to mount, using the two tapped screw holes on either side of the shaft hole, originally used to mount the stock 1:1 feedthrough bushing. The replacement $600 vernier mechanism originally made by Collins employs those holes for mounting purposes.  The 1-100 dial skirt should be discarded since it serves no useful purpose in this application.  A bigger knob, to cover up the outer edge of the vernier mechanism could be used if one is found.  I have never tried it, but the tiny dial skirt used on the BC-375 T/U could be modified by enlarging the hole in the middle, and the rim epoxied to the tuning knob - epoxy sticks well to both metal and bakelite, so the two ought to be able to be easily fused.

This mod wouldn't look as nice as a stock Collins vernier, but it would certainly be less ridiculous than the steering wheel shown in the photo.


Title: 75A-4 with a steering wheel
Post by: Glenn K2KL on June 20, 2005, 03:26:31 PM
Now I know where I've seen that tuning knob... That's the tuning knob from a land of the giants SX-28!!  :lol:  :lol:
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