I'm new here.Howdy. I have a model 60(late style wiring) and did the recap, including bakelites, all out of spec. resistors, coil resistance check, etc.Broadcast band is fine, sharp peaking on IF cans, all seems well over the band.HOWEVER, the "police band" is dead,dead, dead.I cant find the reason.Antenna coil primary was open and I wound (in the right direction)with #30 and matched the resistance to the drawing.Other coils appear fine.I even have another chassis that I compared with.Checked the mica trimmers, bandswitch,etc. All SEEMS fine, but I need a Philco expert (Mr. Rameriz) to sort me out.
Thanks,
Tom[/b]
Posts: 1,703
Threads: 55
Joined: Sep 2005
City: Evanston, IL
Sounds like you have all the bases covered Tom with your restoration, but you will not hear Police transmissions on 30s and 40s sets that have this AM "Police" band.
That small segment of the AM band just above the regular band (1600-1750 or so) used to be the original Police band back in the 30s and 40s. Now Police are in the VHF and UHF bands with scrambled narow-band FM transmissions.
That band is now part of the expanded AM band (1610-1710). Depending on your area you may hear next to nothing, or occasionally one of the new expanded AM band stations in this newer X-band, as it's called.
Chuck
(One of the other Philco experts. ![Icon_smile Icon_smile](https://philcoradio.com/phorum/images/smilies/icon_smile.gif) )
Thanks, Chuck.
I know nothing is on 1650 kc. or up a ways, but the band on the 60 goes from 1500khz -4mhz., and even with a signal generator cranked, there is nothing.However, if I turn on a work light with a dimmer, there is plenty of hash.
Tom
Posts: 13,776
Threads: 580
Joined: Sep 2005
City: Ferdinand
State, Province, Country: Indiana
Hi Tom, and welcome!
Sounds to me like your oscillator is not running on the "police" band. Did you rewind the oscillator coil primary? And if so, did you use the same number of turns, wound COUNTER-clockwise? The oscillator coil in the 60 is a bit more "finicky" than many other Philcos of this era. I have the specs for the number of turns for both coils around here somewhere (when I rewind a coil, I write down the number of turns and such for future reference).
The primary of both antenna and oscillator coils should be wound with 38 gauge wire; the secondaries (if needed) usually get 32 gauge. #30 would probably be O.K. for the secondary, but not the primary.
Check the band switch itself for possible dirt and corrosion. Deoxit is the best for cleaning these.
Another possibility is moisture absorption in your oscillator coil. You may have to remove it and literally bake it in the oven for about 1/2 hour at 200-225 degrees F. Models 19 and 89 are especially susceptible to moisture absorption in their oscillator coils, but it can happen to any set.
--
Ron Ramirez
Ferdinand IN
Ron,
Thanks for the help. I did not rewind the osc. coil, since the resistance measured o.k., and it works well on the standard band.Maybe I will remove it and check for the corrosion problem you have mentioned on the website. Another guy said maybe the 6A7 is not able to osc. on the 1.5-4.0 mc. band. I'll substitute that first.
If I get it going I'll post the solution.
Tom
Posts: 49
Threads: 5
Joined: Oct 2005
Hi Tom,
Do you have a signal generator that you could set to a few test frequencys in that range and loose couple to the radios antenna? Also do you have a fairly decent lengh of wire attached for an antenna?
Just a few thoughts...........
Jerry,
Yes I have a generator that I coupled thru a small capacitor.And for antenna,I tried my 75Ft. outside antenna,nada.
On a suggestion, I exchanged the 6A7 for another tube and got some signals on the low end of the 1.5-4 mc. band, so I think it may be the osc. coil,wire layout, or a 6A7 with internal capacitance or gain problems.
It is a strange one...
Tom
Well guys, I'm back at it again. i put in a new 6A7, and checked everything again, now it works "gangbusters" on standard a.m., and works well on top end of other band, around 4 m.c., but no where else. I either can't make the osc. function or it won't track on the higher band.
Any new ideas? if not I'll put it back in the cabinet and forget it.
Thanks, Tom
Users browsing this thread: 2 Guest(s)
|
Recent Posts
|
An attempt to remove the Field Coil from a G speaker
|
Mike;
I've only run into a speaker with an open filed coil twice, and they were on newer speakers from the 1940s. One ...Arran — 12:48 AM |
An attempt to remove the Field Coil from a G speaker
|
Arran
Yes, this is my plan for now and what do I got to lose, this is not even the speaker from this radio, but one o...morzh — 10:44 PM |
An attempt to remove the Field Coil from a G speaker
|
Mike;
I would unwrap the field coil, and see if maybe there a break near one of the ends, like where the coil wire att...Arran — 10:23 PM |
An attempt to remove the Field Coil from a G speaker
|
...and this is what I did. I fed a little LT into the screwholes with a small brush, and a little on the rim next to the...morzh — 09:52 PM |
Philco 40-120C Restoration
|
I combined the two 40-120C threads together as we like to keep the discussion of the same radio together. It helps with...klondike98 — 09:36 PM |
Philco 40-120C Weak, Distorted Ouput
|
Just checked were I buy tubes price is four dollars. So living in Florid we have a local source for tubes. David David — 09:14 PM |
Philco 40-120C Weak, Distorted Ouput
|
The higher voltage may be due to higher mains voltage. My mains run 120-125AC when the set was new mains would be 110-11...David — 09:09 PM |
Philco 40-120C Weak, Distorted Ouput
|
Thank you for your reply. I pulled a speaker from a Philco 41-221 and received the same result. I used a signal tracer t...bluecap — 08:45 PM |
Philco 40-120C Weak, Distorted Ouput
|
Have you tried a different speaker?
How did you trace the distortion?
How do you know it is weak? What is the reference?...morzh — 08:33 PM |
Philco 46-480 Electronic Restoration
|
Amen to that! Every time I think I’ve captured them all, I realize that there’s another error. My goal is to finish with...jrblasde — 07:00 PM |
Who's Online
|
There are currently no members online. |
|
![>](https://philcoradio.com/phorum/images/bootbb/asb/right_arrow.png)
|