Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Model 60B late antenna coil question
#1

Been working on a late 60B w/ square tube shields. Recapped the set and replaced all out of tolerance resistors. I had to rewind the antenna primary (4 turns) and the outside oscillator winding (counter clockwise, 17 turns). The set is running, but either something else is wrong of it's WAY out of alignment. I can only pick up the station I broadcast thought my sstran (volume is mediocre even when turned all the way up) and can barely pick up anything else using a 6ft wire.

I read in a previous post while searching for coil info, that the antenna coil has a 20 turn section between lugs 2 and 5. Mine measures open. Is this the section directly under the 4 turn outer section?

What I found by Ron:

Re: Philco 60 - Problem with Short Wave/Police Band
I see I never did report back with the correct number of turns in the 60 oscillator coil primary - my apologies.

I'll give details on both coils while I'm at it.

Model 60 Antenna Coil

Primary (outer) winding - 4 turns, CW, bottom to top, 38 gauge
Secondary winding (on the coil form) - All CW, bottom to top. 25 turns from beginning (lug 1) to lug 3. 129 turns from lug 3 to lug 2. 20 turns from lug 2 to lug 5. 32 gauge works well for this winding.

There is also a separate winding inside the coil form, mounted at the top. It is approximately 250 turns, 38 gauge.

Model 60 Oscillator Coil

Primary (outer) winding - 18 turns, CCW, 38 gauge, bottom to top, lug 3 to lug 2
Secondary winding (on the coil form) - All CW, bottom to top. 15 turns, lug 1 to lug 4. 90 turns, lug 4 to lug 5. 22 turns, lug 5 to lug 6 (on top). 32 gauge is OK for the secondary.

To determine which lug is lug 1, 2, 3, etc., hold the coil by the large mounting lug and count the small lugs clockwise from left to right.
--
Ron Ramirez
Ferdinand, IN
#2

Update: I found more resistors that were way out. Funny, some of them were over 20% under value. Anyway, I aligned the set by ear and it is performing much better. With a 3ft wire in my basement I can pick up the 4 or so strong stations in my area and the shortwave has popped to life.


*EDITED*
That means the information in in the quote from Ron is CORRECT
#3

No, jth877, my information is correct - you are incorrect, and I will prove it.

First, let's look at a Model 60 antenna coil as shown on a Model 60 schematic.

[Image: http://philcoradio.com/images/phorum/Pho...t_coil.jpg]

I have numbered each terminal of this coil on the partial schematic above. Notice there not only is a winding between lugs 2 and 5, but if there were no windings between those two lugs, the set would not play unless someone connected the lead to the tuning condenser and 6A7 control grid to lug 2 instead of lug 5. And then, its performance would be iffy at best.

To reinforce this thought, here is a crude illustration of the bottom view of a Philco model 60 antenna coil.

[Image: http://philcoradio.com/images/phorum/Pho...pinout.jpg]

Looking at the bottom side of the coil, where the lugs and mounting bracket are, you count the lugs clockwise starting at the first lug to the left of the mounting bracket, as shown above.

"Top" is a terminal on the very top of the antenna coil, not shown in this crude illustration.

"GND" is the mounting bracket itself, which also has a lug connected to it. The coil will be grounded by the mounting lug and the bolt which secures it to the chassis (ground).

--
Ron Ramirez
Ferdinand IN
#4

My apologies you are correct! I was counting the ground lug as Lug 1. So I was looking between lugs 1 and 4. Now it makes sense. I wish I found a diagram like that when I started working on this thing. At least someone will find it if they search in the future. Maybe a new topic for the website? Problematic coils and their respective schematics?




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Philco 60 Squealing
I seem to remember eliminating a squeal by changing the IF frequency by a few KHz. Not that you should put too much tru...fenbach — 08:48 PM
Philco 42-390, code 121 speaker
These speakers pop up on eBay regularly, even if at bloated prices. Honestly, have not seen many parts on swapmeets.morzh — 08:38 PM
Philco 38-7 Speaker
The put-put is not like the speaker problem.morzh — 08:29 PM
Mission Bell Model 19A Car Radio
Hello everyone,  As mentioned in my last post I was going to see if the vibrator / rectifier section could be persuaded...Antipodal — 08:21 PM
Philco 60 Squealing
Wondering if I did it backwards. If a coil was wound backwards, the oscillator would not work at all. Old school...Chas — 07:23 PM
Philco 38-7 Speaker
4-ohm speaker. Black, Green leads.tludka — 07:00 PM
Philco 42-390, code 121 speaker
#87 on the schematic.  This radio had a 8" Zenith  speaker attached to it when I got it. I do don't know the hist...Stevelog — 06:39 PM
Philco 60 Squealing
I'm pretty sure I now have the litz wire soldered. This did not make any difference. Back in April I rewound the seconda...dconant — 06:25 PM
Philco 38-7 Speaker
Just to make sure, you chose either 4 ohm into 5K or into 10K? (blk-org or blk-grn)morzh — 06:23 PM
Philco 38-7 Speaker
I have let this one sit because of other duties. Now I am back, and I have a couple of questions. I hooked up a Hammond ...tludka — 05:34 PM

[-]
Who's Online
There are currently 4867 online users. [Complete List]
» 3 Member(s) | 4864 Guest(s)
AvatarAvatarAvatar

>