[Milsurplus] WWII Navy RU- Receiver Coils

[Mike Morrow]

Dave, you have some coils sets that could not have possibly been used with the sets you named if configured as you report.  Someone has boogered them up badly.  All should be the standard 4/4/4/4/6, unless you have a coil set for GF CBY-46006.

All RU coils sets (after RU-1, for which I have almost no information) have five sections as you show.  With ONE exception only, the pin number and arrangement per section is 4/4/4/4/6.  The ONLY RU-type receiver that does NOT have this exact same coil set arrangement is receiver GF (CBY-46006), which has the 4/4/4/4/4 arrangement.  The GF is the only receiver in the RU-series which does not have a BFO, and needs two less pins in the last section.

The RU receiver design was almost stable with the 1934 RU-3 CBY-46036, ecxept for adding developing some distinctions to make liaison-only and command-only versions, plus add the extension control box circuitry for the command version.  The RF coil sets from the RU-3 onward were usable in all subsequent RU models, plus RAJ (except RU-8, -9, and -15 wbich used the CBY-46064 receiver with RF tuning ratio of 2).

FWIW, here's a short RU-TYPE RECEIVER SUMMARY:

-Receivers have a high to low RF tuning ratio of 1.5, except where noted.
 (SCR-A*-183/-283 receivers use RF tuning ratio of 2.0)
-Functions of the six tube stages are shown in the third column.

   ---      RU       Other information missing.  Pre Navy Type Number system.
CBA-46000   RU-1     Other information missing.
CBY-46006   GF       RF1 RF2 RF3 RF4 DET/AGC AF.  Used with GF.
CBY-46012   RU-2     RF1 RF2 RF3 DET BFO AF.  Used with GF and others.
CBY-46012A  RU-2A    Same stages.  RF tuning ratio = 2.  Beacon band.
CBY-46036   RU-3     RF1 RF2 RF3 AGC DET BFO/AF.  Used with GF-1 and others.
CBY-46041   RU-3A    Same stages.  Used with GF-2.
CBY-46046   RAJ      Same stages.  Local control, Power 6 vdc or 120 vac.
CBY-46048   RU-4     Same stages.  Liaison service.
CBY-46048A  RU-5     Same 
CBY-46048B  RU-6     Same
CBY-46048C  RU-10    Same
CBY-46048D  RU-11    Same
            RU-12
CW -46048D  RU-18    Same
            RU-19
CBY-46051   RU-4A    Same stages.  Used with GF-3.
CBY-46051A  RU-5A    Same stages.  Used with GF-4.
            RU-7     Used with GF-5.
            RU-13    Used with GF-8.
            RU-14    Used with GF-9.
CW -46051A  RU-16    Same stages.  Used with GF-11.
            RU-17    Used with GF-12.
CBY-46064   RU-8     Same stages.  RF tuning ratio is 2.  Used with GF-6.
            RU-9     Used with GF-7.
            RU-15    Used withe GF-10.

Coil set type numbers CBY-47019 to -47028 were assigned to CBY-46006.
Coil set type numbers CBY-47030 to -47039 were assigned to CBY-46012.
Coil set type numbers nt-47065 to -47077, -47088, -47098, -47099, -47105 to -47108, -47112, -47202 to -47204 work with receivers nt-46036, -46041, -46046, -46048*, -46051*.
Coil set type numbers CBY-47128*, -47143 to -47148 work with receiver CBY-46064.

Receiver CBY-46064 is identical to receiver CBY-46051A except for having a RF tuning ratio of 2 instead of 1.5.

Mike / KK5F

-----Original Message-----
>From: David Stinson <arc5 at ix.netcom.com>
>Sent: May 20, 2017 12:35 PM
>To: milsurplus at mailman.qth.net, ARC-5 <arc5 at mailman.qth.net>
>Subject: [ARC5] WWII Navy RU- Receiver Coils.
>
>Re: Coil sets for the WWII Aircraft RU-series receivers.
>
>Have manuals for RU-2A, -5, -8, -13 and -16.
>The coil sets for all of these, when examined with
>the coil rightside-up, label to the right, counting
>the coil contacts from front to back, are:
>4, 4, 4, 4, 6Dn (contact gap down, BFO coil).
>This is also the configuration in my RU-15 receiver.
>
>I made the assumption that all the RU coil sets
>from RU-2A and following were the same
>configuration.  Finally piled-up my stash of
>RU coils and surprise- there are three 
>seemingly incompatable coil configurations.
>In this photo, the "front" of the coils is to
>the right and I count them right-to-left.
>https://goo.gl/photos/Lh4PRy9WiHQn4DWt9
>
>One configuration looks like that 
>for SCR-183 and will plug into that rig,
>though I don't know if it works there.
>It would seem there is no BFO in these.
>That configurtion is 4-4-4-4-4.
>The third has two 6-contact: 4-4-4-6Up-6Dn.
>
>I have coils for:
>
>4-4-4-4-6Dn
>RU-5, RU-7, RU-12, RU-13, RU-15, 
>RU-16, RU-17, RU-18.
>
>4-4-4-4-4
>RU-7, RU-11, RU-12, RU-18, RU-19
>
>4-4-4-6Up-6Dn
>RU-6, RU-12, RU-16, RU-18
>
>Note that RU-7, RU-12, RU-16 and RU-18 all have 
>multiple configurations, -12 and -18 having all three.
>-18 and -19 were supposedly for Liaison use,
>so "No BFO winding" makes no sense.
>The coil nomenclature tags give the "correct" 
>coil numbers.  
>i.e. RU-16 4-4-6 and RU-16 4-6-6 have 
>the manual-listed coil numbers like CW-47112.
>
>The 4-4-4-6Up-6Dn coils do show some
>evidence of being "Ham-burglered."  Was there
>some CQ article on modifying these with an 
>extra BFO coil?
>However, the 4-4-4-4-4 coils do not look
>as though they have been molested.  A mod
>to get them to work in SCR-183 receivers?
>The RU-16 manual does not show 
>the 4-4-4-6-6 configuration.
>
>What do you think?  Is there an explaination
> or did someone "ham-bone" these coils? 
>
>Does anyone have RU-6, RU-7, RU-11,
>RU-12. RU-18 or RU-19 manuals
>that can shed light on the original coil contacts 
>or explain the multiple configurations?  There's usually
>a photo of the contact side of the receiver coil
>set somewhere in the first 14 to 18 pages.
>
>TNKS OM ES 73 DE Dave AB5S