RE: Some early digital proportional history  
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All Forums >> RC Airplanes >> Vintage & Antique RC >> RE: Some early digital proportional history
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RE: Some early digital proportional history - 9/29/2007 3:46:23 PM   
ukengineman


 

Posts: 52
Joined: 4/1/2006
From: London, UNITED KINGDOM
Status: offline 		Encoder of the F&M Digital 5 was self starting. Red button was battery test on the meter. Cost of the early proportional gear was extremely high in real terms back then.

(in reply to HighPlains)
       Post #: 51

RE: Some early digital proportional history - 10/5/2007 7:52:24 PM   
jaymen


 

Posts: 239
Joined: 3/26/2003
From: Mission Viejo, CA, USA
Status: offline 		The modulation was the same on most post 1965 transmitters, but the frame rate, and neutral pulse width did vary on some models. 1.5 milliseconds and 1.7 milliseconds was used for the neutral pulse width, hence some servos will not quite center, but you can adjust the servo feedback pot to solve this.

On the AM stuff, as mentioned above, a pulse reverser like Ace, Royal, and McDaniels sold works fine. My servo cycler has a reverse pulse switch too.

The F&M Digital 5 had Digimite servos, failsafe type, Bonner circuit boards, I have one. There are 32 little balls in there, take it apart in a shoebox, or spend hours looking for them....... Yes, they are real slow. A split supply of plus and minus 3 volts(6 volts total) helps a little. The Bonner 4RS had 4 wire plastic cased, harmonic drive servos, but they too were slow. I had one recently, NIB, but sold it on eBay as it was just too flakey to deal with.

Sorry, I got confused, it is on FM receivers that the modulation pulses get reversed with high, or low side crystals....too many types of radios and I get crossed up!!

I should have know the difference between a Slylane and Skyhawk...having flown them in flight school, but I guess I'm slipping, there is no future to this old age thing!


The Sampey 404, and the earlier Astronics had a "start" button to kick off the ring counter, pretty crude but it was state of the art back then.

I heard recently that Bob Dunham had a little Taiwanese honey on the side, she worked at that bar in Garden Grove. He used to make alot of trips to the orient....hmmm, what was he up to??

_____________________________

Did you charge the transitory remitter batteries ?

(in reply to ukengineman)
       Post #: 52

RE: Some early digital proportional history - 10/22/2007 4:49:10 AM   
HighPlains


 

Posts: 2665
Joined: 3/2/2003
From: Over da rainbow, KS, USA
Status: offline 		Well Russ, I guess that I will try your scheme of flying a modern airborne with a vintage transmitter. I picked up a '66 Kraft transmitter that's on 27 MC recently. I guess it will work with a Futaba R124H four channel AM receiver. I think I will replace all the electrolyic caps, redo all the internal wiring to the pots and battery, and add a new battery pack. That and redoing the logo, and it should work as good as new.

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In politics if you want anything said, ask a man. If you want anything done, ask a woman - Margaret Thatcher

(in reply to maxpower1954)
       Post #: 53

RE: Some early digital proportional history - 10/22/2007 6:13:26 AM   
maxpower1954


 

Posts: 169
Joined: 11/17/2005
From: Rock Hill, SC, USA
Status: offline 		High Plains, funny you should mention my idea - I flew the Shoestring this afternoon for the first time in four months with the 1970 MRC (Futaba) F-700 TX. Solid, flawless performance. The sticks are longer than I'm used to today, which gets a little crampy after a while.

I would be careful using the Futaba R-124. I tested one last year in the Wingo guinea pig. It had slightly less than half the ground range of the older R-114(now discontinued) about 90 feet compared with 200 feet for the R-114 with the Citizen-Ship DPT, antenna down. I flew it anyway, practically out of sight with no glitching, but I would check it out in some POS airplane first. Futaba only claims a range of 600 feet, but that's what they said about the R-114 and it's definitely a full-range receiver.

The R-114 AM is the way to go, but it's hard to find now. BUT, the HPI RF-2 receiver is in production and is an R-114 built for HPI by Futaba. I've used one and it works fine. Thanks to Frank Schwarz for sending me one for flight test. Ebay seems to have RF-2s all the time, and they can be had from Horizon Hobby new for 40 bucks, from A Train hobbies for 35.

Even as we speak, Ron Ellis is restoring a super clean Heathkit GD-47 TX I got off a certain auction site. From 1968, I think it was one of the last radios to use Bonner sticks.

Is your new Kraft identical in appearance to the metal box one you have on 72? What stick assemblies? Pictures please! Russ Farris


< Message edited by maxpower1954 -- 10/22/2007 6:40:41 AM >

(in reply to HighPlains)
       Post #: 54

RE: Some early digital proportional history - 10/22/2007 6:43:02 AM   
HighPlains


 

Posts: 2665
Joined: 3/2/2003
From: Over da rainbow, KS, USA
Status: offline 		Thanks for the receiver tip. I'll get the HPI RF-2 then.

The Kraft is a single stick with the rudder on the top rear of the case, rudder trim next to it, and throttle and trim on the right side. It needs the logo reapplied and a new handle on the stick for cosmetic restoration. Here is a picture from an old Kraft ad, and a picture of it next to the the two stick Kraft.

Attachments
Click to see fullsize image.
Click for fullsize 		Click to see fullsize image.
Click for fullsize


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In politics if you want anything said, ask a man. If you want anything done, ask a woman - Margaret Thatcher

(in reply to maxpower1954)
       Post #: 55

RE: Some early digital proportional history - 10/22/2007 7:05:17 AM   
maxpower1954


 

Posts: 169
Joined: 11/17/2005
From: Rock Hill, SC, USA
Status: offline 		Pretty neat, HighPlains! I don't think I've ever seen an control arrangement like that before. I would find that awkward to fly...Russ Farris

(in reply to HighPlains)
       Post #: 56

RE: Some early digital proportional history - 10/22/2007 7:13:15 AM   
HighPlains


 

Posts: 2665
Joined: 3/2/2003
From: Over da rainbow, KS, USA
Status: offline 		Yes, I have to agree that it is awkward but possible. I certainly liked my series 70 Kraft single stick much more, as I flew with it for about 10 or 11 years. I've still got it in the original packing crate. What switched me over to two stick was pylon racing when I finger glitched the rudder during a turn and planted a plane. The "salad bowel" stick worked great for sport flying.

< Message edited by HighPlains -- 10/22/2007 7:14:43 AM >

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In politics if you want anything said, ask a man. If you want anything done, ask a woman - Margaret Thatcher

(in reply to maxpower1954)
       Post #: 57

RE: Some early digital proportional history - 10/22/2007 10:10:23 PM   
fizzwater2


 

Posts: 800
Joined: 8/16/2004
From: Paola, KS, USA
Status: online 		What a neat pair of old Krafts, Highplains!

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no matter where you go, there you are..

(in reply to HighPlains)
       Post #: 58

RE: Some early digital proportional history - 10/23/2007 3:05:07 PM   
grotto2



Posts: 328
Joined: 2/3/2003
From: Palm Bay, FL, USA
Status: offline 		The thing I have against the R114 is that it is only four channels.

I tested my F&M transmitter on it and verified that the first channel is actually dead (unused). That means I really need a six channel Rx.

The R114 decoder could be modified for additional channels, but it's not a real easy task....a bit of a hack. I presume from what you say, Russ, the HPI is the same.

It would be really nice to have a good dual conversion 6-8 channel 27mHz receiver. I had hoped Silvertone would have one, but even theirs is single conversion and a bit pricey.

http://www.silvertone.com.au/mark22-smrx.htm

.....Edit: Maybe not that bad, though. My calculations put the price at around $112 American, and they do claim 10kHz bandwidth.

< Message edited by grotto2 -- 10/26/2007 5:13:19 PM >

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I finally got a tattoo. It reads, "Born too loose."

(in reply to maxpower1954)
       Post #: 59

RE: Some early digital proportional history - 10/25/2007 8:08:32 AM   
Michaelj2k



Posts: 312
Joined: 9/15/2006
From: Newark, DE, USA
Status: offline 		Highplains,
I used to fly one of those Kraft single stick radios, every component of the system was gold anodized. The stick you are referring to was a aluminum rod drilled and tapped then attached to the assembly. As I recall it was maybe about three inches long, rounded on the end and anodized red. Got pretty good at coordinating rudder and aileron. Now that I think about it, the stick was probably one of the type used on the two stick radio but without the thumb grip. That was for the guys converting over from reeds who would fly proportional with their thumbs. Orbit did it right with the three axis single stick control. Finally, Kraft introduced the three axis stick with the introduction of the Gold Medal system in 1968.

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"He''s crazy Lew, he builds toy airplanes."
Waco Brotherhood #6

(in reply to grotto2)
       Post #: 60

RE: Some early digital proportional history - 10/25/2007 2:14:24 PM   
HighPlains


 

Posts: 2665
Joined: 3/2/2003
From: Over da rainbow, KS, USA
Status: offline 		Thanks Michaelj2k. I have not found any good pictures of the transmitter, except for ads showing the Bonner stick assembly instead of the open gimbal. Any idea of the diameter of the rod, and was it tapered?. I suppose the anodized red was to match all the other levers.

The two stick has a ID plate on the bottom like all the later Krafts, with a serial number 2262 engraved on the plate. Due to the servos (KPS-9), it must have been produced at the very end of the series. The single stick has a sticker inside with I think (very very faded) typed on it the serial number 542. Not too many produced over a two year period, but I would think the single to be fairly rare.

_____________________________

In politics if you want anything said, ask a man. If you want anything done, ask a woman - Margaret Thatcher

(in reply to Michaelj2k)
       Post #: 61

RE: Some early digital proportional history - 10/26/2007 2:08:49 AM   
Michaelj2k



Posts: 312
Joined: 9/15/2006
From: Newark, DE, USA
Status: offline 		Yup, I think it is a rare transmitter as everyone flying pattern preferred the Mode 1 or 2 two stick open gimbal radio while the single stick was sold to the sport flyers. As far as the stick diameter, the rod was a constant diameter, maybe 3/16 inch to 1/4 inch and from 3 to 4 inches long. It's been a long time and I'm not exactly sure but the dimensions are ballpark.

_____________________________

"He''s crazy Lew, he builds toy airplanes."
Waco Brotherhood #6

(in reply to HighPlains)
       Post #: 62

RE: Some early digital proportional history - 11/2/2007 10:19:32 PM   
smallrc


 

Posts: 40
Joined: 1/11/2003
From: Elkland, MO, USA
Status: offline 		Lots of good information on this thread! I fly a Bicentennial Series
7 channel Kraft system regularly, 72 mHz & 53 mHz. Hope I never
have to give up the yellow tx's for new technology!

Kenny

_____________________________

SmallRC, the Kraft Collector

(in reply to Michaelj2k)
       Post #: 63

RE: Some early digital proportional history - 11/12/2007 5:35:14 PM   
boberos


 

Posts: 433
Joined: 4/22/2005
From: peterborough, ON, CANADA
Status: online 		Maxpower1954,
You could try doubling the antenna length on that Futaba AM Rx. I believe it was intended for cars, so Futaba only gave it a half of an antenna.
That Rx is 1st choce for others using old 1960's vintage propo transmitters.

(in reply to smallrc)
       Post #: 64

RE: Some early digital proportional history - 11/13/2007 3:30:56 AM