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Maynard, the parts list shows them as one physical part. I thought I mentioned that some time ago, all going back to the S-40b or before. Sent: Tuesday, February 11, 2025 11:44 AM To:

So the same would be true for L6... Also, I wonder if under some circumstances (~1/2w antenna) shorting out that 1k resistor would improve Band 1 performance.? Seems like it would be a voltage

The very nice revised schematic by dexterdxer@... dated 3/14/2019 shows a dashed line around the two halves of coil L3. I think that if the original Hallicrafters schematic had included some

Hi, Don and Richard, I agree that the S-40B and S-85 are identical with respect to the input circuitry. The contrast I see is between those two and the S-40A, which is entirely different. Two issues I

Richard, Maynard, Emanuele and anyone left. agree Richard ,numbering is beyond my mental gymnastic ability. I am now convinced that for Band 1, L3 top couples the signal-in to L3 bottom where C4 is,

To Maynard and Don: I have gone over the schematics of the S-85 and S-40B and after staring at them for quite a while now can't make sense of it. I am missing something, what? The two are pretty much

Providing only two primary windings in the S-40B as opposed to 4 such windings in the S-40A may have saved money, but it might also have made the receiver more useful to at least some owners. Whatever

Richard, how do you define “performed”? More than anything, the front end needs to remove images; if it doesn’t do that, does it really perform well? The IF cant remove images. As you know the

Hi Richard this topic began with an S-85, and has wandered off with good reason to its predecessors as well as the S-99. Maynard mentioned the 40A and 40B so I don’t know what ”it” means. From

There are many changes from the S-40A to S-40B and later versions. Its obvious that cost cutting had something to do with it but I think the B had more modern circuits in several places. I think it

Yes, it is balanced on Bands 3 and 4 above 5.3 MHz. But the two coils for the lower bands have no primary windings and terminal A1 connects to the top of the coil for either Band 1 or 2. When the

I have an S-108 in my restoration queue and I noticed that the schematic is exactly the same as the S-85! Maybe there is a small difference somewhere I missed but it's not obvious.? That "wrong" Band

It is a balanced imput. Redraw the input circuits to show the actual wiring without the switch. -- Richard Knoppow Los Angeles WB6KBL SKCC 19998

I think the S-40B and S-85 are constructed so that the link from the antenna terminals couples to the two highest bands as well as the low bands. Redraw the circuit to see how this is done. I find

It would be difficult to rewire the S-40B to allow balanced input on Bands 1 and 2. The S-40A uses transformers with primary and secondary windings and resonance of the secondaries on all four bands.

Well! The email system seems to have stripped the tabs out of my chart, but I hope it's readable. 73, Maynard W6PAP

Hi, Don, I measured my S-40B's antenna terminals with an old analog VOM, so don't take the measurements to be exceedingly precise, but I think that they do tell the story: Band A1-A2 A1-G A2-G 1

Hi, Don, I did check the S-40A schematic and it shows all the input coils wired so that on all bands they can function as balanced input circuits unlike the S-40B and S-85 that leave terminal A2 open

Maynard https://bama.edebris.com/download/hallicra/s85/094-901347-E_Hallicrafters_S-85_S-85U_Mark_1A-1B_Operating_And_Service_Instructions_Feb1958.pdf I did not get that far. My coils between the

Hi, Don, Oops! I lost track of who was doing what here. I have only your diagram, not the S-85 manual, but note that when the bandswitch is set to Band 1 or Band 2, antenna terminal A2 is not