Lubricating Stiff Portable Radio Antenna?

[Ishmael]

I just got a Sony "Earth Orbiter" 10 band portable radio and am in the process of cleaning and restoring it. It has a retractable antenna that is intact and unkinked, which when fully extended can both pivot and rotate to bring in a signal. I have noticed that the antenna takes a fair amount of effort to extend and retract and I assume that any lubricating grease/oil has likely dried in the 30+ years since this radio was made.

Here are my questions:

Should I clean, and/or, lubricate this antenna, and if so what products work best to clean the antenna and then lubricate it?

Is this best done with the antennal removed from the radio case,or, can this be done with the antenna still in the radio case?

This is a beautiful machine. If you would like to you can see it in my post "Ground Control to Major Tom" in the General Audio forum. Thanks for any help you can provide.

 

[loopstick]

Here's a convenient link to your thread:


Ground Control to Major Tom

I'd just put something on a rag and wipe the antenna when fully extended. Vaseline, 3-in-1, WD-40, electronics lube, etc. I'd leave the antenna installed in the radio just because the more you mess with that old plastic the greater the chance you might crack a threaded post.

Your Sony is cool because it has classic looks. Later on Sony came out with some great SW radios, one was desired for synchronous detection. But they were so miniaturized I just couldn't bring myself to buy one. I got the Sangean instead:

________________

 

[Brian]

On my auto antenna I wipe them down with a rag and alcohol and then another with a bit of WD-40. You could use something like a contact cleaner with lubricant. You need to get residue off, can and add a lubricant/conductor/protector.

Over the years I have restored many frozen electric antennas.

 

[jdurbin1]

Hirschmann used to supply little foil packages with silicon grease in them, you tore the ends open and then ran the package up and down the extended mast to grease it, then wiped off any excess after cycling it up and down several times.

That was for their powered antennas but the same stuff works great on manual telescoping antennas. It came in little tubes, too. I still have a couple at home just in case.

Not sure if this stuff is still being sold but here's what it looks like:

Dry silicon spray works too, less likely to attract dust but wears off sooner. I have a can of that stuff from Kent Industries.


John


P.S. Brian is right on cleaning first, if it's dirty... if just dry/stiff and no signs of crud at the joints, you can go right to the lube.

 

[Silversleep]

I have used gun oil, Ballistol oil, auto wax.After a while it would need more lubricant so i gave up.

 

[Ishmael]

Thanks loop for adding the post and to everyone else for your suggestions, of course I should have thought of car antennas as whatever they sell for automotive antennas will work just fine for a radio antenna. The antenna has no corrosion in the chrome plating and no rust. I opened up the back and the battery bay is pristine, I don't think anyone ever used it other than on its AC cord. I also discovered that in addition to the attached antenna you can wire external antennas whose wires can be routed through a gap provided for in the battery cover. Now I just have to find an owner’s manual/service manual to understand all the uses there are for this radio. Thanks again for your help.

 

[Brian]

The jack symbol in the 2nd photo while a bit blurred looks like the international symbol for a tape output. This was not uncommon.

Do you need help with the screw terminals in the 1st photo. Is so, we can help as these are easy to understand for most of us.

 

[Ishmael]

Brian, yes any help is welcome. Other than our Sansui TU-717 I have not dealt with a portable radio in 50 years, let alone one as sophisticated as this one. I believe you are correct that the outlet above the AC power cord is a tape out though I don’t know what kind of mini-output jack it would take. I am guessing a small headphone jack might work (using my cheap micrometer and eye balling the hole it appears to be 2mm in diameter)? Looking at the external antennas those on the right side are labeled from top to bottom “SW” then “MW LW” followed by the symbol for ground. On the left side the top is labeled “FM AIR PSB” followed by the symbol for ground. I am guessing that the right side is for “SW” short wave and “MW LW” medium wave/long wave radio signals? While on the left side “FM” is FM radio, “AIR” is for airplane frequencies and “PSB” is public service broadcasts, fire, police, etc.? These would also correspond to the Band dial scales as they are labeled “PSB-Public Service Band”, “Air-Aircraft”, “FM-Frequency Modulation”, “LW-Long Wave/Weather”, “MW-Medium Wave” and then there are 5 different “SW” bands. I think I have figured it out how the “Time Zone of the World” map/slider work, putting the slider on the area for Pacific Standard time zone, at 9:00 o’clock, our current time, and following the slider over to Tours France, where my daughter and granddaughters live I get 1800 hours, or, 6:00 pm which is the correct time for Tours (I have a little desk clock set to their time for making phone calls). So I think that’s how this works?

 

[Brian]

That seems correct as you surmise. The jack was commonly called 1/8" and today the metric equivalent is very close to 3.5mm. Sometimes no problem using the 3.5 but sometimes they need a bit of contact bending to get a good connection. Most are mono as I suspect yours ls and designed to go into the tape record input. If none, you need.tlax the signal voltage and then use the mic. input. RS used go sell the cables both with and without the paddiing and mono and stereo. The stereo version will work fine.

The FM antenna as it has the ground lug is likely to be for a 75 ohm cable. In the past with these radios I have just used a ribbon dipole that is 300 ohms without a balenciaga and it will work. The other antenna are long wire for general use or wire specifically cut to length for the frequencies covered depending on how serious and deep you want to get into it. Do understand that this can open up a whole new world not related to stereo or audio and you can soon be comparing antenna designs as deeply as speaker design, setting alarm clocks to alert you to listening to stations and sell cards hanging from the walls. And nothing like wondering if a RME or Hammond or E.H. Scott or Hallicrafters will do better and whether to restore a Transoceanic or, look for a Grundig 800 for a "portable".

 

[onemug]

The FM antenna as it has the ground lug is likely to be for a 75 ohm cable. In the past with these radios I have just used a ribbon dipole that is 300 ohms without a balenciaga and it will work. The other antenna are long wire for general use or wire specifically cut to length for the frequencies covered depending on how serious and deep you want to get into it. Do understand that this can open up a whole new world not related to stereo or audio and you can soon be comparing antenna designs as deeply as speaker design, setting alarm clocks to alert you to listening to stations and sell cards hanging from the walls. And nothing like wondering if a RME or Hammond or E.H. Scott or Hallicrafters will do better and whether to restore a Transoceanic or, look for a Grundig 800 for a "portable".

Went elsewhere with it.

 

[Ishmael]

Thanks Brian, ah obsession, isn't that what hobbies are for?