[jerryhawthorne]

Morzh, you might try this link for grommets, I have had luck with them, nice soft and compliant. http://www.renovatedradios.com/parts.html#rubber

As for the shadow meter, some good stuff on it on the Philco Phorum. May have an open coil, perhaps a stuck movement. Strong signal should move it if all is right.

Regards, Jerry

[morzh]

Jerry, thanks,

Yes I found them yesterday when googling, through a thread here on Philcoradio, Ron gave the link.
But I did not see anything for 18 tuning cap there, so I tried Lowes. Well, two more washers per screw will do it I think.

It's a good question if the RF stage would work well with the coil open in the SM. It is bypassed but it may lower the gain as now the primary of the RF transformer is in series with a 2.9k or so resistor.

Will see tomorrow, today I am beat.

[jerryhawthorne]

Again, not the smartest. I tried to find a link to your schematic as many of those meters have a bypass resistor so if the coil is open, the radio will still work. Pop a wire off the shadow meter and take a measurement across it. See if the coil is open. I hope not. I'm not up to winding those coils!
Regards, Jerry

[morzh]

Will do it tonite.
I don't like coil winding either.

[morzh]

Well, yesterday night I stopped by Home Depot, bought two extra rubber washers per screw and that did the trick: the cap now no longer wobbles though it does feel springy, which is OK I think.

As for the shadow meter's coil, I buzzed it yesterday, it shows practically a short which I think translates into the "coil is OK".
Actually maybe I do not know how to operate it. Will look at it tonight. I have a feeling it might be OK.

[DKinYORKpa]

Could you post a picture sometime of what was left of your grill cloth? And do you still have a P/M from me?

[morzh]

Yes I still have it.
As for the pics, there is practically no cloth left.
Whatever I posted before, this was it.
Look at the start of this thread, there is. picture here the pattern is somewhat visible.

[jerryhawthorne]

Morzh, how is it going, have not heard from you in a while.
Jerry

[morzh]

Jerry

Actually not that long a while
Been busy, work, family, ya'know....stuff.
I have not touched it in a week, as I come home late, and all I have energy for is just being alive in front of the TV.


Anyways, today I figured why my Shadow meter no workie-workie.
The reasons are many:
1) The lamp was bad. Somehow stupid me did not realize that the meter employs a separate lamp and it is no longer being ..well....incandescent. The lamp that lighted the scale was, and I thought all was copacetic. It was not.
Well, I used a bayonet lamp of the same format in the scale lighting and I moved the scale lamp to the shadow meter (the scale uses a clip, but the shadow meter uses actual screw socket).
2) at that point I had to adjust the lamp to produce the shadowed pattern. Then I realize the bar does not move at all.
3) I measured the coil again, and then I thought that the coil should not be a short, it should be about 1Kohm (roughly 1000 feet of 40 gauge wire times 1 ohm/foot). Then I saw a non-typical wire under the chassis and it was shorting the shadow meter coil. Hence the short. I opened it. The coil is open. No continuity at all.


So, now I have to see how to remove the coil itself and rewind it. I read the instructions at the Philcorepairbench, but the removal is not clear.


Anyone?


PS. ANother option - to buy another shadow meter. Separately.

[morzh]

OK, the shadograph came back (I posted some prelim. results in the thread about it).

Here's what I don't get:

1. At some point of the discussion about this Philco it was suggested it is the ver. 124. Which it probably is as the volume control hookup (different between the two and in my case it looks like 124 one) seems to confirm that.
Now correct me if I am wrong but the 124 does not have the band switch.
Well, mine does.

2. Also 124 shows a bypass 2.9K resistor across the shadograph, and mine did not have it.

So I am a bit confused which version I have.

In any case, I disconnected the 3K resistor I installed in parallel to the shadowhgraph, and it did not make a whole lot of difference.
It works but I thought it'd get more narrow. When the radio tunes to the local station the shadow becomes about 5mm (0.2").
I have zero experience with these so I don't know if it is normal or should I try for a better result.

And, it seems like while doing all that I found I have something akin to a bad connection. While tuning in I have sometimes temporary jump in volume and the shadow meter gets narrower. This seems to correspond with the area where the tuning cap is and the tube onits right. When rocking the tube I got that same result but then tuning cap behaves similar. I cleaned the panel with Deoxit, did not help.
Oh well, I'll figure it out tomorrow.

And one more question:
The tone control regulator shows (in 124) the switch as part 53 and three caps as part 54. When referring to the BOM for the 54 it will say "condensers inside 53". However I have the part 54 shown as a backelite cap at the chassis bottom view (and it is there). It is indeed connected as the first out of the three caps on the left (0.05uF) on the schematic.

[Ron Ramirez]

Morzh, what frequencies do you have on your dial scale?

If you have 52 to 150 in large numbers plus 1.5 to 4.0 in small numbers above that, then it is an 18 Code 121.

If you have 53 to 170 in large numbers and no other numbers, then it should be an 18 Code 124 (AM only).

If you have 54 to 170 on the lower of two scales plus 4.2 to 12 on the upper scale, both sets of numbers the same size, then you have a 118.

[morzh]

I have the first one, it is I think 121.

It is my impression that the schematics I have are for 118 and 124. The first one does not explicitly say it, it just says "Model 18".
So when I saw the discrepancies in the volume control circuit and someone here suggested it was 124, I checked that same circuit and it was the same as mine, so I decided it was 124. What I have been oblivious to all this time is the fact that it does have the band switch and 124 does not.

Also the resistor across the shadograph - mine does not have it and 124 does.
I will have to look for the sch for 118, I guess, although the differences are minor when it comes to the circuitry - seems like the same tubes, and more or less the same parts' positioning - so far I successfully used 124 chassis pics and sch.


Q: am I expected to hear anything on the 1.5 - 4.0Mc band?

[klondike98]

Here's a link to a frequency allocation chart. http://upload.wikimedia.org/wikipedia/co...ectrum.pdf

[morzh]

So this band today is fairly useless. I think it works but even if it did not I guess I wouldn't be worried about it.

[morzh]

Today decided to look for that bad connection. Took me about 2 minutes to find it and 10 minutes to repair.

It happened to be the wire that goes from the antenna coil to the tuning gang. The wire is going through a hole in the chassis, right under the backelite cap #6. After some tapping and touching, I touched that wire and the effect became very pronounced. The volume increases by about 6dB or so, and the tuning shadow really narrows. Though the tuning remained intact, I guess because of the IF stage. But the sensitivity would drop.
First I thought it was bad soldering, but then something told me it was not. I lifted the #6 cap and looked at the place where it was going through the chassis.
So what it was, the wire (low voltage type) rubbed a bit against the sharp edge of that hole and was shorting to the Chassis.
I remedied it with a piece of heat-shrinkable tubing, and the problem went away.
Now the tuning eye really narrows when tuned to the local station.

I put the chassis back in the cabinet. Will let it play awhile.

PS. There is one single crack in the grillwork; I think in the summer I will ask for some advice while trying to repair it.