[hsusmann]

Correction to my post above regarding stuck shadow meter vanes:

I re-read Brenda's post and she actually said to use Liquid Wrench not WD-40 to free up stuck vanes.

I have not tried either yet on my shadow meter. It is a little sticky sometimes but not too bad.

Herb S.

[Pithicus999]

When I first started this thing over a year ago, I seem to remember finding a wire going to that antenna coil that was not connected. Also, there were two ‘Tabs’ coming off the antenna coil that didn’t have any wires connected, one of them I assumed was the GND tab since there wasn’t a wire going to GND. In hind sight, I should have left the wire and the two tabs alone until I knew what the H**l I was doing (which from my experience won’t be for another several years jk) because if I would have forgotten that I hooked up the wires I may not have questioned to even check them.

The only way I found out that they were hooked up incorrectly was due to the fact that I drew out a picture of the coil and its tabs, numbered the contacts on my drawing, and then following each connection numbered the same contacts on the schematic. When I went to take measurements, the measurements where these two wires were supposed to be going were contradicting each other. The only way that can make sense (I thought) was if I was measuring a different wire than I thought I was, so I swapped them, re-measured and all connections checked out with relatively small resistance.

I’m not sure about the vane in the shadow meter…it seemed to move very freely, I even blew on it and it moved around very well. One thing I just noticed that I forgot to mention because I think I’m used to more modern electronics, and that is that the other bulbs is burned out (non-shadow meter bulb). Looking at the schematic a current does flow through this bulb to a pin on each of the #78 tubes. I think once I replace the bulb that will make a difference and then I’ll see where things are at.

Thanks Herb and Jerry you were both right about checking the coil and about where to check, thanks again. I’ll probably spray the vane anyway, just to make sure.

[Pithicus999]

I replaced both light bulbs and she’s humming away nicely. However, I do have a shadow meter problem and I’ve watched a few youtube videos to try and see what can be done.

Last week I took it apart and attached a small 9 volt battery to the contacts as I tapped the lead to the battery. It seemed to move each time. Then, when I hooked everything back up it worked a bit, then sporadically, then didn’t work at all.

I took apart the shadow meter again to take a look. No broken leads, both were hooked up to the two wires. The 9 volt battery trick didn’t work at all this time. I blew at the vane and it seemed to move about freely. This leads me to believe that the coil has a break.

The wires are super thin, like smaller than a hair it looks like. Can I buy a small coil like this? Or do I need to re-wire this thing????

Thanks.

[hsusmann]

Do you have continuity on the shadow meter coil? (Ohm meter)

[Pithicus999]

I don't believe so, but I can check with the multimeter to be sure.

[Pithicus999]

No continuity.

[hsusmann]

If you have no continuity on the coil then there is a broken
wire somewhere. If it is not right at the terminals of coil then
it may be somewhere buried inside the coil and it will have
to be rewound.

I think there is a web page over at the Philco Repair Bench
website that describes how to rewind those coils. You need
about 1000 ft of very fine magnet wire and alot of patience!

Someone else here on the Phorum may have more detailed
rewinding advice also.

Herb S.

[morzh]

I sent mine to Antique Radio Society of Alabama (I could probably find exact name, or you could find my thread on that) - they re-wound it for me. Works fine. Was 50 bucks.

[jerryhawthorne]

As Mike indicated, they do a nice job on this stuff. For that price, I would loose my mind (practically gone already) not to mention my eyesight trying it myself. Great suggestion. Of course the other alternative is to see if someone has one to sell to you.
Jerry

[Pithicus999]

I tried winding it myself (before I saw these responses!)

but there is another problem as well, here's a video

http://youtu.be/8N8mA5y4Kgo

[Pithicus999]

Any idea on what's going on in this video?

http://youtu.be/8N8mA5y4Kgo

The set is working, just not a really strong sound coming out of it.....

[hsusmann]

I watched your youtube video. It is a bit hard not being there myself to see exactly what is going on but...

Re: the higher plate voltages: what is your current AC line voltage? Modern line voltages are usually higher than they were back in the day. You might try measuring your line voltage and see if that helps explain the difference.

Re: touching the Grid pins. Your probe is probably acting as an antenna. What antenna do you have attached to the radio? If there is no antenna at all then this might make some sense. you should attach a long wire to the antenna terminals if you don't already. Probably 20 ft is OK but 100+ feet going up into a tree is best.

Again, without being there I am shooting in the dark a little on this.

I didn't understand your comments on the 42 tube voltages, perhaps you could elaborate? It's a little hard to read the paper on the video.

Hope this helps!

Herb S.
Ithaca NY

[Pithicus999]

Hi Herb,

Thanks for the advice. When you say 'AC line voltage' are you referring to the power coming in? If so, i've got it plugged in so that'd be 120...not using any kind of slow voltage generating machine...don't have one. Interestingly enough, the volts coming into all the tubes are supposed to be 6.4 V yet all mine are 5.9 V so not sure why that is.

Currently I have only about 20 feet of antenna (per your suggestion a ways back). I think at this point i'm gonna just pack it up and take it back to my dad's place. Maybe put a longer antenna wire on it and call it good. I do have another radio that I bought online that I'll probably start working on next year or something. I've got a lot to learn still and I plan on reading a bunch of electronic books as well as meeting up with people.

so, until then...

[hsusmann]

OK, Perhaps someone here with more first hand experience with your particular model can chime in here.

When I go to nostalgia air all I see is model 18 code 124 so I don't know if that's close enough to your radio or not.

What I meant by line voltage was indeed the AC voltage at your wall outlet. Did you actually measure it with an AC volt meter? If not, you should check it. It does vary somewhat regionally.

If you are only getting 5.9v instead of 6.3 for the filaments that sounds a little low but it may be in tolerance for that radio, I'm not sure. It is a bit strange that your B+ is high but your filament voltage is low.

Some radios have a switch on the AC line input for line voltage (ie 110v or 120v). The schematic I just looked at does not have such a switch.

I assume you are using some kind of fairly accurate digital multi-meter to measure these voltages?

I think there is something wrong somewhere if the signal dramatically gets louder if you probe those grids. Have you done any kind of alignment on the radio? I see there is a trimmer cap (#5) on the RF Amp grid LC tank and another trimmer (#10) on the 6A7 grid tank. I can imagine if those are off then the front end gain will not be what it should be.

So, without being there in person it's hard to troubleshoot via postings but these are the kind of things I may look at if you are having low signal levels.

Herb S.

[Pithicus999]

Thanks Herb.

It's the 18 (code 121) the 124 is a bit different.

And actually, I put this project on hold for now. Which is to say that I dropped it off at my dad's house, it works perhaps not as well as it should but until I retire there is a sh@tload of other stuff I need to do before I work on that radio again.

Thanks for the help, and thanks to the rest of you as well! I'll be visiting these sites from time to time because I do have another radio a philco 38-38 (that I actually bought while I was working on this one, the excitment got to me as I've read on these here threads can happen from time to time).

I plan on starting up work again on the 38-38 sometime next year 2015...so, until then!