Epic Restoration Of A Ten Tec Triton IV – Part 3

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Cosmetic Restoration of the Triton IV

photo of the nicotine and Sharpie patina A patina of nicotine and Sharpie

In a previous post, I finished repairs on a Ten Tec Triton IV transceiver. Now it was time to address the grubby cosmetics of the radio. The radio had obviously been used as a mobile. Markings had been added to the front panel in Sharpie, and there was a yellowish film on the panel. For mobile use, the previous owner had added a microphone clip and a 12-volt power switch — both mounted with sheet metal screws into the plastic sides.

Why add a power switch? Because the volume control power switch is only suited for light duty. Several of the early Ten Tec radios were configured for use with matching external power supplies, and the power switch on the volume control was meant to switch 120-volt power in that supply. Because the radio can draw up to 15 amps during transmit, an external switch or relay is needed to control power in 12-volt mobile systems.

The remains of a label or identification plate were visible on the top cover, and the paint was chipped on the heat sink in back. And generally speaking, the radio just needed to be cleaned.

Disassembly

The Triton IV is easy to open for service. The top cover is removed first, by sliding it towards the back of the radio after removing two self-tapping screws on the back lip. It can be a snug fit in the channels of the two plastic sides, but gentle persuasion will work.

photo of the Back of a Triton IV Back of a Triton IV

Next, we flip the radio on its top to remove the bottom cover. Start by removing the 4 screws that attach the speaker cover. The cover comes off to reveal a 2-5/8″ round speaker, similar to those found in transistor radios of the era. Be careful not to damage the speaker, as 2-5/8″ is an uncommon size, and they can be hard to find. Lifting the speaker out of panel, one can slide it into the radio by fitting it vertically into the two extra holes at the front and back of the speaker mount.

Close-up photo of the speaker Close-up of the speaker

Six self-tapping  screws  (three on each side) and six machine screws (two in the back and four near the front) are removed . You must also remove the two front feet. The bottom cover can now be slid off in the same fashion as the top cover.

The front panel and sides are next. Start by removing all the knobs. Most attach to D-shaped shafts, but three, including the main tuning knob have a single set screw. Ten Tec used to include the tiny hex-key wrench needed to remove these knobs in a small parts kit, but you may have to scrounge one up. The dial skirt is next, and it will slide off with the main tuning knob removed.

Top view of the Ten Tec Triton IV Top view of the Ten Tec Triton IV

The front panel is captured by slots in the plastic sides, and they are removed next. There are two screws through the back panel on each side, and one screw near the top front that grabs the aluminum chassis on each side. The sides can now be removed and the front panel is free. Be careful to not damage the three wires that connect the front panel to the main chassis. They can be unplugged, but the wires break off of the connector very easily. Happily, if this happens, they can be re-soldered.

Cleaning the Front panel

Since I had to replace an LED on the front panel (as mentioned in an earlier post), I had already removed the black plastic escutcheon. There are a mix of eight screws (self-tapping and machine) to do this — so pay attention to where they go. The front panel was now bare and ready for cleaning.

When working with old equipment, it’s important to use the gentlest cleaning method possible because solvents can attack paint.  For example, the plastic “Ten Tec” emblem is easily damaged by solvents. Therefore, I usually start with Formula 409 cleaner. It’s often enough to be effective and hasn’t damaged anything for me yet. It’s possible to make it more aggressive by adding some ammonia, but use that with good ventilation. 409 did pretty well removing the yellowish haze. It also works pretty well at cleaning finger grime on knobs.

photo of the front panel All cleaned up All cleaned up

Sharpie is more challenging. It is a permanent marker after all, so stronger measures are needed. Xylene Solvent is an effective way to remove Sharpie, but be careful. Start by testing a small, hidden area with any solvent before proceeding. Even so, use it only where needed. I like to use a Q-tip and work carefully on small areas. In this case, I was able completely avoid the silk screened lettering. Finally, a warning: Xylene should only be used in a well-ventilated area with a respirator effective for organic compounds. Avoid exposure to the fumes!

The clear plastic window and escutcheon can be cleaned with Armor All. It works well on most plastics for both cleaning and restoration. It will not remove scratches however. Be sure to use a soft rag (like an old cut-up t-shirt) when cleaning plastic.

Painting the Amplifier Heatsink

The easiest way to paint the heatsink is to remove the final amp module from the radio. To do this, you first remove the phono plug that connects the driver board to the amp input, and then unsolder the other wires (like power, etc.) from the back of the module. I usually take a picture with my Smart Phone so I can remember where to solder them back on. Four self-tapping screws are then removed from the back of the module, and it will slide out of the radio.

photo of Freshly painted heat sink Freshly painted

I used a Scotch-Brite pad to remove the loose paint and then masked the back parts of the module with Blue Painter’s Tape. Everything else can be sprayed with paint. Krylon “Fusion” satin black was a good match for the existing paint. I like Krylon because it sprays easily and dries quickly. The module was ready for re-installation about an hour later.

Recovering the Top

photo of the Vinyl covering comparison Vinyl covering comparison

Many of the early Ten Tec radios used vinyl adhesive wrap on the top aluminum cover. On this radio, the black leather textured vinyl was damaged by a label that had been removed near the back, so recovering was in order. It’s hard to find an exact match for the original covering, but I was able to find one that is very close.

Removing the damaged vinyl is pretty easy, and a little bit of heat from a heat gun can help. In this case it came off cleanly. Before recovering, it is important to remove all adhesive residue and any other dirt or grease. Prep-All is an effective solvent for this.

photo of Recovering the top Recovering the top

Once cleaned, I simply cut a piece of the vinyl covering a little larger than the top cover. Starting at one end, I removed a little of the protective paper from the vinyl and adhered it to one side of the cover. Working slowly and carefully, I pressed the vinyl to the cover a little at a time, making sure to avoid air bubbles. A plastic dough scraper is helpful for smoothing the vinyl onto the cover as the protective paper is peeled off.

photo of the new covering The cover is like new

Once finished I pressed the vinyl over the back lip. Two small cuts are needed to accommodate the amplifier module. The vinyl is then smoothed down on the underside of the cover, but only on the front and back edge. the sides are trimmed flush with the aluminum edge.

Repairing the Side Panels

photo of the Side panel with holes Side panel with holes

Last, but not least, I needed to patch the holes in the side panels left by the mounting screws for the mic holder and power switch box. I used a little plastic epoxy for this, mixed with some ground black plastic. I was hoping to fill and texture the holes so they would blend in. Not surprisingly, the repairs were pretty obvious, so I decided to use the black vinyl to cover each side panel. This works well, because the side panels have insets that were originally intended for this treatment. There are early Ten Tec products with vinyl on the sides, although they abandoned this practice later on.

Well, that’s it — and I think it turned out pretty well. I really like giving old equipment a new life, and this radio should be good for another 40 years!
photo of the radio With a new power cable: Ready for delivery With a new power cable: Ready for delivery

8 Replies to “Epic Restoration Of A Ten Tec Triton IV – Part 3”

  1. Tobacco gets everywhere, Mics are the main culprit of the smell as they are right below your nose.
    For me first priority is a mic strip and wash with warm soapy water.
    Also cotton buds and isopropanol do well on the innards of the mic.
    Well impressed with that vinyl covering Jim makes a very proffessional restoration

  2. Followed all three parts with interest as I recently acquired a Triton 544. The CW filter is present but the noise blanker is missing. Physically it just needs a good cleaning, no extra holes or magic marker but several missing screws.

    1. Glad to hear you have the CW filter. These radios are really good for CW, assuming you have the filter. The noise blanker is pretty rare in my experience. It was most useful for impulse noise associated with mobile use, so if you’re not taking the radio on the road, you probably won’t miss it.

      Good luck with your restoration!

  3. Great video series, Jim. I just rescued a Triton IV Digital from a metal recycler and will try to get it going. Its far from a shelf queen. While the insides are really clean, and someone either did or planned to replace caps (there are pencil markings next to each one showing dimensional alignment), the case is well used and some of the printing around a few knobs is worn off. Time to break out the labeler. It has the optional NB and CW filter, but no power cord or mic. I read the internal power switch is a weak point and can’t handle full power? Did you power yours via a Ten Tec PS, or direct from a different PS or battery? Any help is appreciated. 73 Cliff W3KKO

    1. Hi Cliff — glad you found something useful here. You are correct that the internal power switch on the Triton IV is not robust enough to handle 12-volts at 15+ amps needed when transmitting at full power. It is intended to switch the 115 VAC line of the power supply. If you want to switch 12-volt power, Ten Tec recommended you use an external relay. My shack is entirely 12-volt and powered by a solar power system so I used an automotive fan relay. Search on Amazon for “Bosch Style 5-Pin 12V Relay Switch [SPDT] [30/40 Amp]” and you should find it. In this arrangement, the Triton IV internal switch applies power to the relay coil, while the relay switches 12-volt power to the radio. You might also want to add a fuse or circuit breaker. The original power supply had overcurrent protection to prevent damage to the radio’s finals in the event of a severe antenna mismatch. Without current overprotection, you run the risk of blowing finals. Good luck on your project! 73’s, Jim — update — There’s a new post describing this power relay arrangement.

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