[R-390] R-388 question

[Jim Whartenby]

Thanks Tom
I have this schematic but it does not show S-119 aka the Break-in switch.  

C-2 of TM 11-854 describes the mod but there is no schematic that shows S-119 in series with K-101's coil.  I'm beginning to think that this modified R-388 might have been part of the GRC-26/B or C shelters.  The operation of the Break-in switch is mentioned in TM 11-5829-202-10 aka TO32R2-2GRC-26-151 on page 49.  But all illustrations of the R-388 in the manual show a speaker jack instead of the Break-in switch.

Actually, the dreaded previous owner has removed K-101 from this receiver and used the terminal strip on the rear apron for another purpose.  When I pull the front panel I will check to see if the wires to S-119 are tucked out of site.  I should be able to replace K-101 from my junk-box so I might be able to return this particular R-388 back to almost original configuration.

The rear of this receiver had seen some rough handling.  Some sheet metal bending was needed to straighten the rear apron and the fuse holder needed replacement along with a new line cord.  I am going through two R-388 found at the Orlando Hamfest two years ago.  Both have the Break-in switch.  I have a 51J-4 that is in need of three ferrite slugs.  The hope was that one of these two receivers would be an organ donor but so far it looks like at least one is serviceable.
Regards,
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.  Murphy 

    On Saturday, April 6, 2024 at 01:29:51 PM CDT, Tom Frobase <tfrobase at gmail.com> wrote:  
 
 Pretty simple attached from 388 schematic.
On Sat, Apr 6, 2024 at 10:41 AM Jim Whartenby via R-390 <r-390 at mailman.qth.net> wrote:

On the bench is a R-388 with a defective Break-in switch mounted in place of the speaker jack on the front panel.  Turns out that the switch was not connected to the wiring harness.  A check of the various R-388 manuals on hand does not show how this switch was connected.  Change 2 of TM 11-854 mentions the Break-in switch but there is no other information.
Does anyone have a link to a schematic that shows this Break-in switch?Regards,Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.  Murphy
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