Radio Control SPORT/AEROBATICS
Ron Van Putte
You may have wondered what happened to the Ace Silver Seven encoder modification to my Kraft KP-7Z transmitter, since I announced that one was under construction several months ago. I'll report on my experiences, not so much to satisfy your curiosity, but to let you know some of the "do and don't" factors of the Silver Seven—and to inform you about the integrity of Ace RC.
My Silver Seven encoder was built before Christmas 1981, and when it was first turned on it didn't work. Undaunted, I assumed that the main integrated circuit (IC) was faulty. After I purchased another IC (NE 5044) from Ace RC and installed it, it still didn't work.
At this point I should tell you that I was attempting to use the Silver Seven encoder to drive my original 1975 RF section—for three reasons. The reasons, in order, were:
- I wasn't sure that the Ace RF section would fit in my transmitter.
- The Ace RF section won't drive a panel meter like my old RF did.
- I am basically frugal (a tightwad) and didn't want to buy something new that wasn't needed.
After several months of extensive troubleshooting, I still couldn't find anything wrong with the encoder. It just wouldn't work. Then I went on a trip to Long Island to visit the Grumman Aerospace Corporation and ran into Bob Aberle (Flying Models technical editor) and George Myers (Model Aviation Radio Technique columnist). After telling them of my experiences, they both laughed and told me that the same thing had happened to them when they built one of the early production models of the Silver Seven. They assured me that I had missed soldering one of the board-to-board interconnects (these connect components on the top of the board with circuits on the top and bottom of the board). Flushed with that comforting information, I rushed home and spent two evenings checking for bad connections. There weren't any. Boy, was I frustrated!
I let the whole thing sit for another month and finally swallowed my ego. A long letter was composed describing what I had done checking out the encoder, and off it went to Ace RC, along with the sick transmitter. When I hadn't heard anything from Ace in more than five weeks I was really angry. Then, just before six weeks were up, the transmitter came back with an explanation from Paul Holsten, the chief technician at Ace. It seems that my 1975 RF section required an amplifier between it and the Silver Seven encoder, since the RF section required more voltage to drive it than the encoder put out. Ace had written to Kraft for the service manual on the 1975 KP-7Z transmitter and telephoned Kraft technicians to discuss the best way to build and install the amplifier.
Unfortunately, the same day my transmitter returned, the amplifier quit working. I bundled it up the next day and returned it to Ace. After waiting a reasonable time for the transmitter to get back to them, I called and talked to Paul Holsten about what had happened. He confirmed that the amplifier wasn't working properly and recommended that I give up the idea of trying to use the old Kraft RF section. Instead, he suggested that I replace it with a Pro Line RF section. The reason for suggesting the Pro Line RF section was that it would drive my panel meter, unlike the Ace RF section. Unfortunately, it also required that the antenna be replaced, since it had to be a different length than my original antenna.
A short time later my transmitter returned from Ace, and I eagerly tried it out. It worked—and it worked great! The Pro Line RF section was smaller than the old Kraft one, and Ace RC had done a beautiful job integrating it into the transmitter case.
The "proof of the pudding" is the answer to the question, "Would you build another Ace Silver Seven encoder and install it in a transmitter?" That's easy to answer—I certainly would. In fact, by the time you read this, my 1974 Kraft KP-7Z transmitter should have a Silver Seven encoder and Pro Line RF section installed.
There are several reasons I would:
- 1974/1975 KP-7Z transmitters are among the best Kraft put out, in my opinion. Ron Chidgey–designed stick assemblies are superb.
- I used Pro Line Competition Series transmitters and still use Kraft Signature Series transmitters.
- The transmitter is the heart of a super radio system. The Silver Seven encoder enables the modeler, with some talent in soldering and following directions, to get a super system a lot cheaper than buying new systems.
- I like to be able to tell people I built mine myself, with a little help from Ace RC.
A bit of advice for modelers thinking about incorporating the Silver Seven encoder into an existing transmitter:
- Write a preliminary letter to Ace RC to find out if the Silver Seven encoder is compatible with the RF section of your transmitter.
- Order and read the instructions for building and installing the Silver Seven encoder. That way you can decide if you feel you're up to the task.
Probably the most foolproof way of getting the Silver Seven is to order a complete transmitter already assembled by Ace. Somewhat less foolproof, but easier than trying to integrate the Silver Seven encoder into an existing transmitter, is to order a Silver Seven transmitter kit. Either way you do it, you'll have a system that you can be proud of for many years.
I've always had substantial respect for the products which Ace RC sells, but my experiences with the Silver Seven transmitter modification gave me a view of another aspect of Ace. During all my contacts with them, their attitude was refreshing. Everyone seemed interested in getting my system working the way it was supposed to—as one modeler to another.
I'm sympathetic to the concerns of competitors about contest procedures (I don't like the turnaround pattern either), but I'm only one person. Let's all get together and make our opinions known to our Contest Board members.
Another sore subject with fellow competitors is the foul-up on the changes to the Sportsman and Expert class maneuver lists in the 1982–83 AMA rule book. There has got to be a way to alleviate the frustration and anger competitors feel toward flying the old maneuver schedules for the next two years.
One obvious way to change the situation is for Contest Directors to announce in the Competition Newsletter's Contest Calendar and in their own contest flyers that the Sportsman and Expert classes will be flown at their contests in accordance with the revised lists that everyone thought would be flown in 1982 and 1983, rather than what's in the rule book. I recommended this action to several Contest Directors who will have contests later this year, and I look forward to seeing if they carry through with it rather than complain about the situation.
Ron Van Putte 111 Sleepy Oaks Road Ft. Walton Beach, FL 32548
Transcribed from original scans by AI. Minor OCR errors may remain.
