Help with Identifying & Sourcing A Few Parts

[BCR 570]

Greetings

I am looking for a little assistance in identifying and sourcing a few parts for an upcoming project.  There is so much knowledge here on this forum that it is worth a shot.

#1 - I was looking for a Pyle switcher type headlight with number boards but several here suggested one from the Life-Like SW900/1200 and I now have some on the way - thank you Jim!


#2 - I need to find a suitable part for the rear light which is a little larger than the Miniatures By Eric single light casting we use on Canadian diesels.  It also has a curved bezel surrounding the lens door.



Would anyone know the diameter for this type of light, and a suitable part available in N Scale that I am not aware of?


#3 - I need to identify and size this contraption on the roof during the 1970s.  I am guessing that it might be some sort of antenna.  Apologies for the grainy images but have cropped from larger photos:





It appears to comprise two circles stacked above each other with vertical supports.  Would anyone know exactly what this device is, and what the diameter would be?  Going to be something approaching 36" I think.


#4 - I am looking for an N Scale running board in the Morton pattern (circular performations instead of the older Apex style rectangular grating) and it needs to be at least 47'-6" in length.

Would anyone know of an N Scale car (likely a more modern one) with this length and style of running board?  Ideally available as a separate part, but if I have to cannibalize, so be it.


Any assistance appreciated,

Tim

[C855B]

#3 - I need to identify and size this contraption on the roof during the 1970s... antenna... Going to be something approaching 36" I think.

My edu-guess is loop antenna for omnidirectional broadcast FM reception, 88-108 MHz. The full picture would be helpful as I would expect both examples to be mounted on passenger equipment serving an entertainment receiver. Loop antenna calculations are complex (and it's been 20+ years since my last antenna design project), so I would go with your guess of ~36" as a reasonable ballpark.

[chessie system fan]

#4 - I am looking for an N Scale running board in the Morton pattern (circular performations instead of the older Apex style rectangular grating) and it needs to be at least 47'-6" in length.

Would anyone know of an N Scale car (likely a more modern one) with this length and style of running board?

Someone will need to double-check me, but I believe the Intermountain PS 4750 3-bay grain car has what you need.

[mmagliaro]

I don't know of a commercial part for that loop antenna, but if I were doing it, I would hunt for a suitable spring from which you can clip two coils, and then either (delicately!) solder some fine wire vertical supports, or just tack them on with dabs of epoxy.
36" works out to 0.225" or 5.7mm.  I think some phosphor bronze coupler or truck springs from one of the large scales would be perfect for this.

[Missaberoad]

Tim #2 looks identical to the housing of the ditchlights on our GP38-2 and SD40-2 units. Cmr makes a 3d printed part, I've never seen it before tho...

https://www.cmrproducts.com/Locomotive-Detail-Parts-Ditch-Light-without-Housing-p519536596

Its actually pretty close in size to the single beam rear light on the SD40-2s that the MBE part is based off... the MBE part is a little undersized tho.

[BCR 570]

Thank you all for your replies.  Just received a nice overhead image also showing the antenna:




I am also looking for Detail Associates N 8005 bell if anyone has a package to spare.


Tim

[Missaberoad]

Someone will need to double-check me, but I believe the Intermountain PS 4750 3-bay grain car has what you need.

Correct, ATSF models also makes one but I believe theirs is for a 40 foot boxcar.

[peteski]

That antenna looks like 2 separate loops of wire held aligned by the uprights. (not a spiral).  While probably not easy, you could probably fabricate this from soldered wire.   Yes I realize how small it would be in N scale.

[C855B]

Thank you all for your replies.  Just received a nice overhead image also showing the antenna:

That changes everything. The choke wasn't discernible in the other shots. This is a transceiving antenna which appears to be a loop dipole, likely in the commercial HF bands below 30 MHz, a/k/a "shortwave". Knowing that the coil is there it would be really helpful to have the service context. In other words, a full picture of the equipment it's mounted on.

Judging from the roofwalk it's closer to 4' in diameter, which in running a quick computation would put the resonant frequency at roughly 20 MHz, or 10 MHz depending on how the trap (choke/coil) is configured. That frequency determination makes a certain amount of sense, so again I'd go with 42-48" in diameter. The frequencies and polarization would also be consistent with an inductive trainphone system.

[BCR 570]

I found several images online of similar antennas described as FM loop antennas so yes.

The context:  mounted on the roof of Sperry detector cars during the 1970s.  Wont be 48" as that would extend from running board to edge of car.  Roof is 9'-9 5/8" wide with 18" wide running board down the centre.

Wondering if this would be for communications or perhaps for entertainment system in crew lounge (which would be directly beneath it)?  The crews lived on these cars for many weeks at a time and a skookum entertainment system would seem to be a prudent creature comfort . . .

Tim

[C855B]

OK, 1970s helps nail it down a little better, and that it's possibly for a crew lounge alters the perspective. So, "entertainment" has to be the right answer.

Yeah, 36" is a good enough guess, and I now suspect it's a brute-force TV antenna. VHF TV bands in that era were 54-88 MHz and 174-216 MHz. TV reception in mobile applications is tricky because the signal is horizontally polarized and usually received with directional antennas you might remember from long ago. The two loops probably are each handling a band, and the "choke" is adding resonant length to the top loop for the lower frequencies. It would also be okay-ish for broadcast FM.

Antenna design back then was all slide rules and paper, so not a lot of sophistication here. Loops done this way were an attempt to make TV antennas non-directional, and they performed poorly for a host of reasons. I guess given the situation they must've been thankful they had anything at all.

[BCR 570]

Thank you for your insight; much appreciated!

Tim

[Missaberoad]

One of the old engineers when I hired on once piloted with a Sperry car back in the 80s, his memories involved them having a TV along with a supply of "gentleman's special interest" videos and literature. 

[Angus Shops]

One of the old engineers when I hired on once piloted with a Sperry car back in the 80s, his memories involved them having a TV along with a supply of "gentleman's special interest" videos and literature. 

Ha ha ha…



…gross.

[mmagliaro]

That antenna looks like 2 separate loops of wire held aligned by the uprights. (not a spiral).  While probably not easy, you could probably fabricate this from soldered wire.   Yes I realize how small it would be in N scale.

Point taken.  Honestly, I was suggesting just clipping a 2-loop section from a small spring, with a few fine vertical wires soldered to it and calling that "close enough" even though the prototype isn't a spiral.  I suppose you could clip two separate coils, slip them over a form (like a round toothpick), gently bend each one vertically to take the spiral out of it, and then solder the little wires
between them.  Doing it all on a wood round form would keep them round and lined up.  I advocate using the spring coils because making perfectly round little rings of wire in this size will instantly deform out of round by the time you even get the thing mounted on the engine, unless they are "springy" wire like phosphor bronze.  And making perfectly round coils of phosphor bronze wire is very difficult.  The coil spring has done the hard job for you.