eHam Forums => Elmers => Topic started by: NI1V on November 29, 2002, 01:55:57 PM

Title: Which tuner cleaner?
Post by: NI1V on November 29, 2002, 01:55:57 PM
Dear Forum Elmer's,
I have a Hammarlund HQ-170A-VHF that has been in a smoke filled shack. I would like to clean the noisy switches but need "tuner cleaner" that will handle this sticky build up but is non-flammable and dries with no residue. Internet searches have produced some results but unbiased third party input is what I need. I have several older radios that I would like to service as well and don't want to make a horrible mistake.
                  73 de NI1V-Jeffrey

Title: Which tuner cleaner?
Post by: K5CEY on November 29, 2002, 02:13:27 PM
 What ever kind you use, be sure it is of the non lubricated type. It's been a while, but a good one was "Blue Shower" from MCM Electronics. I test it by spraying some on my hand. It should leave no oily residue. Ammonia and water works well on the chassis and other parts. Used to buy 6 inch medical swabs (Like a long single ended Q Tip) from the medical supply house. These are great for cleaning in tight places like between i.f. transformers and such.
                John  K5CEY

Title: Which tuner cleaner?
Post by: K9IUQ on November 29, 2002, 06:14:22 PM
I Have tried most off the tuner cleaner brands and the one that stands out is DeoxIT. It is superior to other brands and is priced rather high but worth it. Do a search on the Web for more info and where to buy it.

Stan K9IUQ

Title: Which tuner cleaner?
Post by: AC5UP on November 29, 2002, 09:24:31 PM
Give some thought to the concept of 'no residue' for a moment... Is a truly dry and lubrication free rotary switch a desireable goal?

If it were mine, I'd blow out the worst of the crud with CRC's Lectra-Motive spray (available at most auto supply stores, look for the alternator and starter motor on the label) as it's cheap and works well, then finish it off with a light spray of WD-40... Yes, WD-40.

The amount of residue (after a day or two) won't be enough to attract or hold dust, but the residual lubrication will go a long way toward extending the life of the switch. I'd also put a drop or two of semi-synthetic tranny fluid, like Dexron III, or a light lithium grease on the bushing and ball & detent assembly.

Do it right, and you'll have a switch that works well, stays clean, and feels good to operate.

BTW: WD-40 as a cleaner/lubricant for switch contacts and related mechanisms is an approved procedure for Tektronix 'scopes, as long as you control the overspray. It's in the book for the 7xxx and 46x series. No kidding!


Title: Which tuner cleaner?
Post by: K5CEY on November 30, 2002, 11:49:32 AM
For AC5UP: Good point about lubricating the contacts and bushings. I should have mentioned following the cleaning process with a "lube job." WD 40 is fine but it dispenses too quickly and overspray is a problem. What I do is spray some into a small can lid and then apply it to the contacts with a toothpick or Q Tip.
                John  K5CEY

Title: Which tuner cleaner?
Post by: AC5UP on November 30, 2002, 07:33:40 PM
For K5CEY:

I've done a few off-the wall maintenance tricks with good results, and semi-synthetic Dexron III tranny fluid is becoming one of my favorite tools. I used to have an inkjet printer and always kept the little bottles from the refill kits as they make excellent oilers for small spaces. Just avoid filling them beyond 2/3 full as that gives you better control.

I have an R-1051B/URR receiver that's one of the more unique designs I've seen short of an R-390 as it uses small roller chains and sprockets to synchronize the tuned circuits in about three modules. When it tunes you're moving a lot more than a variable cap and, depending on the range, you may be switching the IF lineup as well. The front end has a motorized turret tuner with maybe 18 positions and this adds up to a bunch of silver-plated rotary switch contacts. When I first got it I'd have to occassionally back up a few kHz to give one or more of the switches a second chance to make a good contact.

I fixed that by wetting all the turret fingers with a bit of Dexron III, exercising it, then daubing off the excess onto a paper towel. The chassis is nicely protected against dust (it's a Navy rig) and the interesting part was how much black oxidation came off the contacts onto the paper towel. The contacts definitely brightened up and it's been running FB since. While this may not be the hot tip for a more conventional rig that's not as mechanically complex, here's an experiment in clean & lube that makes a point:

Dig a tarnished silver plated BNC out of the junkbox and give it a rub-down with a paper towel moistened with WD-40 or tranny fluid. It works, and all it takes is just a touch to keep everything sliding smoothly...


Title: Which tuner cleaner?
Post by: WA9SVD on December 01, 2002, 08:14:53 PM
Non-flammable cleaners may be harder and harder to obtain.  Just be careful, read the directions carefully, and remember, even WD-40 is flammable!

Title: Which tuner cleaner?
Post by: KE4DRN on December 04, 2002, 12:06:31 AM
I agree DeoxIt is a great product.

check and learn more about it.

Our Xerox tech (he uses it on HV ps and all connectors) gave me some to try on my older
kenwood 520 and 530, nice and quite pots and no more
pops when you push the switches.  Band switches clean.
so-239 looks like it is new again.

Yes, it is a little more expensive the other cleaners,
the DP5S-6 product, it is a pump spray (no voc content so no hazmat ups fee) and will last a long time.

It goes a long way, just a little drop is all you need.