Bigdipper99

I'm just getting into the RC hobby and am in the process of building my first plane, a SIG Kadet Mark II. I'm trying to do it on a budget and a couple of weeks ago I picked up a complete vintage (1980s? ) Futaba "Conquest" six channel system at an RC flea market for $20, The outfit has the radio, receiver, four S 148 servos, batteries, charger and other misc. parts with most of the stuff appearing to be lightly used or unused, still wrapped in plastic. I've reached the point in the construction of the wing where its time to install the aileron servo in the wing. However, I've noticed that the top of the servo extends above the bottom of the wing. The wing will be installed on top of the fuselage and the servo will be out of sight. However, I'm concerned that the servo could possibly interfere with other servos, linkages or equipment within the fuselage. Am I reading too much into this and seeing a problem that doesnt exist? Can wing servos extend beyond the skin of a wing? Thanks, John

speedracerntrixie

My Feedback: (29)

John, yes on the older stuff it was common practice to have the top of aileron servo occupy the main radio compartment. Sometimes it gets a little tight but as long as there is no interaction your good to go. Here is a great example with my1980 Quickie 500.

Hydro Junkie

I'd be more worried about the transmitter than the servos. I bought a Conquest 4 that is about the same age as the one you bought, mine being a 1986 purchase. The problem is that, back in 1991, the FCC changed the rules on how a transmitter could work and, unless your system was updated, it's probably illegal. Mine has what is known as a "wideband" transmission pattern, meaning the transmission pattern extends, IIRC, 80KHz above and below the frequency listed on the transmitter. When the FCC changed the rules, they required all transmitters to be retuned in order to extend only 40KHz above or below the listed frequency. If your system was upgraded to meet the new rules it should have a gold sticker on it, making it legal. If not, some if not most clubs probably won't let you use it

Bigdipper99

Thank you for the response. When I bought the system, I was unaware of the inspection requirement. Fortunately, the previous owner had it inspected and it passed. The radio has the appropriate gold RF inspection sticker on it. I would have been pissed if I had to junk the thing!

Bigdipper99

I appreciate your response, its a big help, particularly with the pictures. What brand of servos are you utilizing in the plane in the photos?

speedracerntrixie

My Feedback: (29)

Those are MKS HV69 servos. Back in the day mainly the radio manufactures made servos, today we have a few companies that just make servos. The MKS are my preferred brand at the moment although completely overkill for this airplane. The HV69 is a wide voltage servo that will operate on 5V to 8V, has metal gears, ball bearing output shaft and 149oz of torque at 7.4V.

From a beginner standpoint the S-148 servos are a great choice and will fly your Kadet just fine. As you progress you may gravitate to a specific type of aircraft, perhaps warbirds, giant scale aerobatics, pattern. Or you may just stick with vintage sport airplanes. Point is specialty airplanes require specific servo performance and at that point you will know what to look for.

I have to give kudos to Hydro, I didn’t think of the narrow band change in 1991, I’m glad he did and your radio has the correct specifications.

mgnostic

In Re the original question, there is probably plenty of room in a Kadet fuselage. A further thought on the transmitter is that you will want to change the battery if you haven't already. Transmitter batteries are kind of out of sight, out of mind and it may take enough of a charge to work the controls but old batteries definitely have a shelf life. One upside to old radios is that you seldom have to wait for a frequency pin. I was one of the last hold outs on 72 mHz in my club and I switched over 5-6 years ago.

Hydro Junkie

I would have to agree with you Matt, there is a lot of room in the cabin. It has more room than the Kadet Jr does and the Jr's got plenty for three S48s installed on this Futaba servo tray:
https://www.towerhobbies.com/product...CABEgLNTfD_BwE
Since the S48 is a standard sized servo, that tray will work with pretty much any standard sized servo Futaba sells