38-62 - can't get the one station I want to hear!
Posts: 289
Threads: 42
Joined: Jan 2014
City: Jeffersonville
State, Province, Country: PA
Howdy fellas -
Working on a 38-62 that gets stations strong except for one that I naturally want to hear, at 1440. I get all others above and below. I can hear this station just fine with all my other radios. Changed antennas, moved the radio to different parts of the house, all with the same results. Would a dirty contact on the tuner at this exact point be the cause? I've never run into this before where one specific station couldn't be heard. Not even a faint trace of it and another radio next it playing that location strong.
Regards,
Paul
Posts: 2,128
Threads: 18
Joined: Oct 2008
City: Merrick, Long Island, NY
This is tough one, If the set has a loop antenna built in, you might try to rotate direction of set in anotherwise good reception area. Of course if stuff is cutting out at 1400 and there is no reception above it, could be a piece of whatever caught at the top o the blades of the tuning capacitor that you could dislodge patiently with a piece of paper between each gap. If it rubs, it is touching. Try, then come back.
Posts: 16,505
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Paul
Have you aligned the set? As Codefox pointed out, what we need to know if the signal above and at 1440 comes through when you set your oscilaltor to that frequency.
Posts: 1,470
Threads: 97
Joined: Jul 2012
City: Poughkeepsie, N.Y.
Paul Are all the tubes good and strong? A forum member told me when you can not tune in a station in a certain radio dial section a week tube is always the problem. It helped me on my Philco.
Posts: 893
Threads: 9
Joined: Mar 2008
City: Vieques, PR USA
State, Province, Country: PR
I lean towards the dirty tuner theory. Be sure to clean the clip that makes contact with the shaft as well as checking for plate shorts.
Posts: 289
Threads: 42
Joined: Jan 2014
City: Jeffersonville
State, Province, Country: PA
Thanks very much for the replies.
I can get stations above it. I have not aligned it because I have not yet learned how and do not have the proper equipment yet, although I have watched videos on how. Self teaching myself here and while I'm a quick learner I'm not at that point yet. It did not originally come with a loop antenna, just a long wire. I've since attached a loop antenna on the end of the wire which greatly improved reception but did not bring this particular station in. The station is only 7 1/2 miles away and comes in clear on all the other radios I own. I did test all the tubes on Hickok 500 tester.
I have not cleaned anything yet because I didn't want to take a shotgun approach. I'd rather learn how to methodically troubleshoot these so I can apply the knowledge to other radios in my very modest collection.
Posts: 16,505
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
You need to try alignmet. It is pointless to talk before you try. You may discover things while doing it.
Like the oscillator does not oscillate at some frequencies. Which could be the tube. Possibly.
Posts: 54
Threads: 8
Joined: Nov 2012
City: Wilton, Iowa
Don't want to butt in here, but could the AVC possibly be choking the station
down since it is so close? Probably extra-strong signal getting to the radio.
Jim
Posts: 1,703
Threads: 55
Joined: Sep 2005
City: Evanston, IL
I'd expect if the station is that close, he'd be getting lots of intermod and bleed thru, regardless of strong AVC voltage.
Typing out loud,
Chuck
Posts: 1,106
Threads: 88
Joined: Jun 2011
City: Tacoma
State, Province, Country: Washington
7 1/2 miles is not that close, normally I wouldn't think there would be overload unless the station were beaming down his throat with 50KW. However, there may be some merit to the AVC having a problem. It's possible he's got no AVC action at all, and the radio is overloading on a strong signal.
Does the station sound any better if you tune off center slightly?
Posts: 289
Threads: 42
Joined: Jan 2014
City: Jeffersonville
State, Province, Country: PA
It does not come in at all. I've spent considerable time trying to hear the slightest hint of the station but nothing. I've got it now but it doesn't receive this station. I can get 650 WSM out of Nashville at night which is 811 miles from me. But not this local station.
Posts: 1,106
Threads: 88
Joined: Jun 2011
City: Tacoma
State, Province, Country: Washington
In that case, I would definately check to make sure none of the plates on the tuner are touching. This can be a challenge, as they are quite close together. Do you have static when tuning past this part of the band?
Posts: 16,505
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
Easy. Just put the ohmmeter across the tuning cap and see if it shows continuity.
Posts: 1,106
Threads: 88
Joined: Jun 2011
City: Tacoma
State, Province, Country: Washington
That can surely tell you if the plates are shorting.. but doesn't do much for un-shorting them.  Now THAT'S the challenge.
Posts: 16,505
Threads: 572
Joined: Oct 2011
City: Jackson
State, Province, Country: NJ
First one needs to know if the short is even there. trying to catch a black cat in a dark room is a difficult task.
Unshorting difficulty depends on the radio.
In a radio like 70 or 90 unless a fin is totally mangled, it is not a problem at all - those are huge caps with huge gaps. Then take a small AA5 set...there is a challenge. a gap is like 0.2mm on either side of a fin.
Users browsing this thread:
|
Recent Posts
|
Testing a speaker and output transformer Trutone A2-G
|
Hello murf! I merged the threads. Please do not start new threads regarding the same radio. Take care, - GaryGarySP — 10:21 PM |
Philco 42-345 Restoration/Repair
|
Regarding picture 5 on page 1 of this thread this capacitor is #40 on scematics diagram - 4mF+4mF. Black wire is "-...Vlad95 — 09:01 PM |
Philco 42-345 Restoration/Repair
|
That's a dual 4 MFD, red and green are both 4mfd and black is common negative. You should be able to see them in the pow...RodB — 08:58 PM |
Philco 42-345 Restoration/Repair
|
Can anyone help me figure out a capacitor that has 3 wires coming out of it red and green on one side and a black wire o...osanders0311 — 08:14 PM |
Two small radios from France. Restoration and review.
|
Greetings;
I think that it's possible that the assortment of components was the result of post war parts shortages, a...Arran — 12:18 PM |
Philco model 38 code 121 not receiving signal.
|
Unfortunately I can't inject any audio into the volume control. It is in the primary circuit of the antenna coil, not in...Stormlord5500 — 09:32 AM |
Philco model 38 code 121 not receiving signal.
|
Sounds good Gary I'll do that. I have plenty of stuff like that I can scrounge up. I am still kind of new to all this so...Stormlord5500 — 08:47 AM |
Philco Battery-WWII vintage
|
Seems to me that this a general purpose or radio filament 6V battery of very high amp-hour capacity and very high "...MrFixr55 — 08:08 AM |
Philco model 38 code 121 not receiving signal.
|
You should be able to inject an audio signal such as from a CD or mP3into the radio at the volume control. The set will...MrFixr55 — 08:14 PM |
Testing a speaker and output transformer Trutone A2-G
|
Hello guy's,
Have a Trutone A2-G teledial floor model radio that I am having issues with.
Suspecting maybe speaker or ...murf — 03:25 PM |
Who's Online
|
There are currently no members online. |
|

|