Thanks,

Dave
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:Just started consulting the schematic for that unit, and initially see that they didn’t show the antenna input into the unit, its sort of just left floating.
:Looking to the adjunct model # 51, I see that they gave a very good drawing of a pictorial layout of that specific unit.
:I went back to the Trirdyne schema. . . .wonder why they didn’t designate the unit spelling as tri-a-dyne ?
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:I have now inserted the application of the antenna signal via the Vivid Green inset.
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: I am seeing two RF related coil assemblies, one of which is the [A ] and [B] combination and the other is the [C] transformer. Now I wonder what are the chances are that the [A] and [B] coil combination on YOUR unit is mechanically built the same as the one used on the model # 51 ? , (Which I have, like color inserted, on the drawing to the far right).
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:That unit is showing to be built with a radial honeycomb wound set of flat plane RF coils that can be variably close or loose coupled in their mechanical positioning.
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:If the first RF coil assembly pair is constructed in that way, isn’t that unit wound with such a large gauge of wire (#22…? ) that any working on / repair of it should be no problem at all or it possibly having flux erosion of connections / wire shrinkage and snapping, after time, which should also be repairable..
:The next aspect might be the [C] transformer which I would expect to be made with fine wire and on a coil form which we are used to seeing. Still, one should be able to ohm out the 2 windings to see if there is an open and it possibly also might have problem with a wire interfacing to its terminal, type of problem that may have onset with time. . . .but if exposed, still being repairable.
:In retrospective I would tend to think of the first RF assembly being quite beefy while the second mentioned transformer would be the more delicate of the two,
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:If the set is not picking up any strong locals, have you tried a couple of test leads daisy chained together for a simple short wire antenna and then clipping one end onto the 1st grid of the first tube, thus bypassing the frontal RF tuning and see if any locals
:are coming in then.
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:Units Operation:
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:I am seeing the manner of operation of the set occurring by the initial input from the antenna coming thru the loading coil, such that series inductive tuning compensation can be made to optimize to different lengths of long wire antenna utilizations.
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:The RF then is inductively coupled between A and B to get to the 1st grid of the first tube to be RF amplified and its output ends up at the plate winding of the RF transformer [C].
: It is then coupled to its secondary where it feeds into the 1st grid of the second tube, which will be the detector stage. . . (no chance that the high value series grid leak resistor has opened up. . .is there ?)
:The amplified AF present at the plate circuitry of that stage is then RF cleansed /isolated by using either a phase inverted winding or an RF choke
:at [ D ] and that audio goes into the AF transformer [ E ] an is then induced into its secondary and the AF signal then zips right on thru the low Z [ B ] winding of the RF unit and is amplified this time as an AF signal by that same 1st RF tube and then . . .optionally. . .is taken off as a headphone signal at the plate of that tube [ H ].
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:Should there be no headphones plugged in the headphone connector, its switching routes the AF to the primary of the driver transformer [F] and then induces amplified AF into it secondary so that the second audio tube at the very end, can bring the audio on up to speaker driving levels at [ G ].
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:Comparative Schematics:
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:73's de Edd
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Thanks,

Dave
:That schematic link is close, but isn't quite right. But I happen to have that set, and pulled it out for a look-see.
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:There are two RF coils - one an antenna coupler between the antenna and the first stage, and one between the first stage and the detector stage. The second one has an adjustable RF tickler for controlling regeneration.
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:Both of those RF coils are the exposed basket-weave type, about 3" in diameter, with maybe #24 cloth-insulated wire. Both have variable coupling controled by a shaft.
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:Is one of those coils open, and if so, which one? I think it would be unusual for them to be open - and if so, I would expect it to be at a termination.
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:There are two audio xfmrs. Is it possible that one of them is the one that is open?
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:This is a reflex set. The first triode stage serves as both an RF and an audio amplifier. Easier to understand in principle than it is to follow on the schematic or on the radio wiring itself.
:Doug
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::Doug,
:: I think it's on this page:
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::http://www.nostalgiaair.org/PagesByModel/697/M0039697.pdf
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::Thanks,
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::Dave
:::Dave, can you link us to the schematic, and pinpoint which coil you are referring to?
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:::This is a reflex circuit, so things get a little confusing.
:::Doug
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::::Hello All,
:::: Is this something I can take apart and repair? If not what is a good substitute, even though it may not look the same as the original?
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::::Thanks,
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::::Dave

Thanks,

Dave
:Dave, I have the model 51 if u need the coils or xmfrs just e mail me

Thanks,

Dave
:Dave, just as I suspected: the open xfmr that you describe is an audio xfmr, not an RF xfmr. You can use the 1:2 Stancor A-53 knock-offs sold by AES and RadioDaze. They also sell replacement coils that should allow you to keep the same black Crosley case, but check dimensions first.
:Doug

http://www.philcoradio.com/tech/511spkr.htm

:Hello All,
: If I cannot get the speaker to work, what speaker transformer do you recommend so I can connect a modern speaker to the amplifier.
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:Thanks,
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:Dave
::Dave, just as I suspected: the open xfmr that you describe is an audio xfmr, not an RF xfmr. You can use the 1:2 Stancor A-53 knock-offs sold by AES and RadioDaze. They also sell replacement coils that should allow you to keep the same black Crosley case, but check dimensions first.
::Doug