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SEA 222 “Tune” switch modification

I had the pleasure of a visit from an old friend recently – the venerable and capable Stephens Engineering Associates SEA222 Marine HF radio. We’ve been “friends” for several decades now . I’ve repaired well over a hundred units over the years, and have spent quite literally  d o z e n s  of hours  carefully studying it’s magnificent design.  I can say confidently from a position of experience: It’s an exceptional rig, and holds up well in comparison to modern radios. A customer sent his in for repair, and along the way – quite literally “out of the blue” I had an idea for a fairly simple solution that resolves an operational weakness of the rig: The lack of a “TUNE” button. Most HF radio’s expect do regular day to day business with an automatic antenna tuner, and sport
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Interesting Repair of the Day: Raytheon R20 – vintage 1988!

There’s an old Star Trek episode  – “The city at the edge of forever” where Kirk and Spock end up going back in time to the 1930’s. In their attempt to get back to their own time, Spock tries to repair his damaged  Tricorder using the  available materials of the day – tubes and such.  Kirk’s 1930’s girlfriend discovers Spock’s efforts, and when asked what he was up to, he  responded brilliantly: “I am endeavoring, ma’am, to construct a mnemonic memory circuit using stone knives and bearskins.” I have unashamedly borrowed that expression “Stone Knives and Bear Skins” and use it regularly to describe “vintage” equipment.   Case in point: The 1988 Raytheon R20 radar display that came in the other day.     I’ve worked on a LOT of R20’s over the years, and really thought I had seen
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Automating the ALS-600

I’m only human, so I’m prone to occasionally screwing up just like anyone else. Over the years, I’ve managed to nuke the FET’s in my Ameritron ALS-600 on 3 occasions – and twice it was clearly may fault. For quite some time, I’ve wanted to make use of a program called “DDUTIL” to automate my Ham radio station, simplifying its operation and greatly reducing the odds of me screwing up – yet again. This program communicates with the Flex 5000’s Power SDR program and allows other devices to automatically sync up and work with with the Power SDR software. DDUTIL  is an exceptionally impressive,  full featured and best of all – free program! Check it out – HERE.   While I am not sure – it may work with other radios too. A few weeks ago I completed the process
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Adding USB to the “Fluidmotion” STEPPIR control box.

If you read some of my other posts you’ll understand that I have no love for the ancient RS-232 protocol , and have found that most items that use a 9 pin RS-232 port can be converted to USB.   Most logic level circuits have signals that use +5 volts for a logic “1” and zero volts as a logic “0”. RS-232 takes these 1’s and 0’s and level shifts them to a much higher voltage level – that has both positive and negative potentials – something in the neighborhood of plus and minus 10 – 12 volts. I guess the reasoning behind doing this is to insure that  determinable voltage levels survived long cable runs. In most Ham applications, the cable length is just a few feet – so signal level shifting of this type is completely unnecessary. USB
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The Kenwood TS-480HX Panadapter project – Part 1.

I’ve owned a Kenwood TS-480 HX for quite a while now, but it was relegated to the shelf when I pulled the trigger on the purchase of a Flex 5000A several years back. Don’t get me wrong – the 480 is a GREAT rig, but the spectrum display provided by the Flex makes it the vastly superior radio – at least in my mind. Recently, my wife and I planned a trip to the island of Eleuthera in The Bahamas. This is not your typical tourist island filled with shopping, casinos and frequented by cruise ships. This is a small, quiet island with many beaches (some of them are PINK) that are often all but deserted. MY kind of place – and my wife wholeheartedly agrees. We will certainly enjoy exploring, swimming and checking out the assortment of restaurants. At
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Deflector shields on maximum!

As noted in previous posts – Our Sun is a double edged sword.  In Southern latitudes it is pretty rough on just about everything – especially poorly protected LCDs. Click the photo for a larger image. The photo shown above is a Sun damaged LCD. The polarization film has been destroyed from prolonged exposure to intense UV radiation. It almost looks like someone took a torch to it! This LCD came from a Raymarine E-120, but we see the same thing in units from a wide variety of manufacturers. I’m sorry to report, we see a lot of this kind of damage from older Furuno units – even when their white plastic covers are in place when not in use.   This is a cover for a Furuno FCV-582L. I am not a plastics expert by any means, but I’ve
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Interesting repair of the day – PART 2: NAVIONICS CF CHART CARD REPAIR

In part 1, I described how a defective Navionics CF chart had  damaged the chart reader circuitry in a Raymarine C90W I was working on. My initial thought was “I better throw this damn thing away before I screw up and accidentally put it into another machine and nuke its chart reader”.  My hand was half way to the garbage can when I paused and  thought – “Ah what the hell – take a look”. I grabbed my knife and proceeded to gently pry open the case. I expected the case halves  would be ultrasonically welded together, and was pleasantly surprised to see that it was a snap fit arrangement.  Once the case was apart, the problem was glaringly obvious – AND repairable! It didn’t occur to me at the time that this would make a good IRoD, so I
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Interesting repair of the day – PART 1: Raymarine C90 W

A customer brings in a Raymarine C90W stating it wouldn’t turn on. They have proven themselves to be very reliable, and very few have come in for repair.  I was initially skeptical, so I tried to power it up and sure enough – it refused to cooperate. Later, I removed the rear case and found this: Click on the photo for a larger image.   The internal chassis was like a soggy Florida morning with dew – everywhere. It was nearly time to go home so I decided to leave it overnight to see if some time in the air conditioning might dry it out. Even with the best seals, atmospheric pressure and temperature changes will cause a unit to “breathe”, and ultimately collect some moisture. Since it’s “fresh” water, it’s no where near as damaging as salt water intrusion,
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Interesting Repair of the Day: Raymarine E120 LCD replacement.

The Sun: The prerequisite for all life, and the destroyer of LCDs! The photo below shows what prolonged exposure can do to a LCD – and it’s not pretty.  It looks like someone took a blow torch to this one! Click on the photo for a better view. The large circular “fried spot” is UV radiation damage to the polarization films on the LCD glass. It takes quite a while for it to get this bad. Had the protective cover been in place this would not have happened. Sidebar: We are seeing the same kind of damage to older Furuno units such as the FCV-582L, the GP-1650 and GP-1850 series LCDs – even if the protective cover is in place! The white plastic cover is not enough to stop the intense UV radiation found in Southern latitudes. Coating the inside
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