This looks to be awesome product ... ... here is a possible add on for you ... now that you have the RPM sensor in place ..how about a digital read out on your aux channel ? it could be mounted on the fuse or on the ??????
I would like one for my 260 Duellist that I am building but will have to wait till next month to purchase ..will you have a purchase plan next month?
ARGH!! It did have a digital readout and I removed it based on the feedback from this forum. Everyone wanted it to be $10 cheaper and for go the RPM readout. i.e. now $89 MSRP rather than $99 MSRP with digital readout.
The other good news is that because the display was removed more LEDS we added and additionally the prodution units can detect low glow battery and bad/disonnected glow plug that was possible with the removal of the display. The bad thing is when it had a digital display it would read out RX pack voltage as well as RPM.
If you want the LED display I still have a solution though. I am going to release a helicopter rotor head speed governor for production in a month or so. It has an RPM and Voltage display on it. I was thinking ahead and designed it so that it could also be manufactured as an engine syncronizer. (Because I liked the idea of the RPM readout). So it will be available as a special order about a month later.
Right on thanks for the update ..let me know or the form when you will release the one with the rpm/volt read out love the idea and would pay more to have the added value.
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Joined: 11/10/2002 From: Mary Esther, Florida, FL, USA Status: offline
George:
Your (Twinman’s) earlier post, and your email to me about rudder to throttle mixing is noted,
On one of my earlier twins I built a mechanical rudder/throttle mixer, it gave zero mixing at idle, curved up to maximum at ½, and curved down to zero mix again at full throttle. Throttle variation was fully proportional to rudder deflection. It worked fine, but it was complex and a bear to get it set up. With the totally proportional input taxi was easy, and never got into chasing the rudder. With the set-up on this sync unit giving mix only at less than 20% throttle and limiting maximum mix addition, I don’t think the problem will arise. We’ll see.
At the same time you can still do it your way by using the individual run-up mode instead of rudder mix. You might even like it better since the inside engine will drop to idle leaving the outside engine controlled by the transmitter.
You said in another thread that the inside engine sometimes ran to fuel starvation in a really tight spin if allowed to go to idle. By using the programmable idle set point you can keep the inside engine at a higher setting, but this would affect the normal idle also.
Regardless, I’m sure your “S-A Kid” can figure a way around it.
Also possible the way this unit is set up will be everything you warn about. If so, later units will have the software modified either to correct it or eliminate the option.
Something that has not been pointed out is that the ECU on it is a “Stored program” device, this programming is in an “EEPROM” and can be altered when desired. BW has mentioned programming updates at a later time, anything can be changed.
Bill.
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Real Airplanes have Two Engines AMA 25139 - More than 40 years.
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Joined: 11/10/2002 From: Mary Esther, Florida, FL, USA Status: offline
IT’S HERE!!!
Here are some pictures, first impressions, and comparisons with the EMS/Jomar sync device.
First, BillW needs to assign a brand name to it. For the moment I’ll call it the “BW Unit.”
It’s not quite the size I had estimated, it is 1 5/8” wide by 2 3/16” long. Height is 3/8” to the ends of the LEDs, the highest point. Compared to the Jomar assembled in the supplied box at 1 ½” square by 7/8” thick. The Jomar pictured is 1” at its maximum point, I added the servo sockets to the outside making the difference.
The first picture is the Jomar in its box, the second is the mess of wiring inside the box which you, as the customer, have to install. Jomar expects you to solder all the connections to the board, including the wires from the sensors. And you have to solder the wires to the sensors as well. Since I prefer two piece wings I had to make everything plug in, the sockets on the end, Radio Shack stereo headphone sockets, are for the sensors.
The BW board in the third picture has pin connectors for everything. Nothing to solder, a much “Cleaner” design. Even the sensors are already wired, complete to the connector plugs. The only questionable thing on it is the lack of a solder mask coating which makes a PC board more resistant to damage, either by scratching it or corrosion from the atmosphere. The Jomar has the mask coating. This coating may be added to the production units.
So far the score is two for Jomar, having the box and the coating. But on the other hand the BW doesn’t require you to make the 15 soldered connections the Jomar needs. I think that makes the score fifteen to two in favor of the BW sync device before going any farther.
Finally we see the magnet supplied by BW in contrast with the one from Jomar. The BW magnet is 3/16” diameter and 1/16” thick. Jomar is ¼” diameter and ¼” thick. This is a mass ratio of more than seven to one in favor of the BW. I didn’t weigh them, but I’d guess the weight ratio is about the same. Using the BW magnet the back plate of the spinner should be easily balanced with nothing more than some lightening holes, the Jomar magnet had to have at least two in the backplate for balance, or some other counter weight. Another point for the BW unit. Or really two, since you only use one magnet per engine opposed the two per engine with the Jomar, or three per engine on a four stroke. We’ll call it two points for the moment.
Score is 17 to 2 in favor of Bill W’s sync unit so far.
Now I need to rip the Jomar sensors out of my C-3/10 and put the BW unit in, we’ll see how it stacks up in operation. That’s for the next report.
Bill.
< Message edited by William Robison -- 6/12/2006 11:28:26 PM >
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Real Airplanes have Two Engines AMA 25139 - More than 40 years.
A couple of comments/updates to William Robinson's post...
1. Yes, the production units have silk screen to label all components and connectors and a solder mask to protect the circuit. This is a prototype board just for testing and will be destroyed after testing (right William???)
2. As far as a plastic case, I don't see a need/reason to put it in one. A better solution is to shrink wrap it in heat shrink like most brushless ESCs do today. I was planning on doing that but then I thought the idea of swapping chips via two $0.39 stamps would be attractive which would allow users of the device with no down time with a deposit on ICs (that is assuming that the device stays in low volume and does not move to surface mount) that we could swap chips by mail. This would allow customizations and firware updates to anyone capable of removing a socketed component and replacing it without having to remove the devices and sending it in for a firmware update (I wish turbine companies would do this). I could build a programming adapter users could run from their PC but unless I start selling thousands of devices it will not be cost effective. So I think most RCers would like to have the ability to get a firmware upgrade via regular mail and wrap the device so it doesn't short out anything rather than have it shrink wrapped. Tooling is expensive and I doubt that anyone will ever sell enough sync units to justify tooling to produce plastic cases.
3. Size of the device.... Being a boater (and a man)... I know SIZE DOES MATTER!!! The production unit is 1.6" x 1.9" with a height of less than 3/8". I could probably get this down to about 1.0" x 1.25" if I went to all suface mount. The production unit has much smaller LEDs and the connectors for the servos is the highest part. The production units are < 1/4" except for the connectors. Suface mount has other draw backs though of no socketed firmware updates and requires a higher volume (i.e. 1000s of units for a production run)... But maybe some distributor or Manufacture will call me tomorrow and want a bunch of these. (I am seeing a lot of new twin engined arfs out there)
4. Soldering and connectors... Connecters take space but they allow for removal and exchanges. This goes back to the shrink wrap discussion. I could save almost $4 (which is probably $10 in retail price) in cost by having the receiver and rpm sensors wires soldered onto the board. But then you could not remove the device and wires tend to frey with vibration (especially with bug gas burners). Freyed wires result in failures/crashes. Having sensors and connectors for everything allows people (and me to offer) to get just a sensor and move the device from one plane to another. Additionally, connectors have a much higher reliabilty - especially with age. Finally, on my twins the RPM sensors are installed early in the building process and the wiring is permanent.
I ordered three samples of the production PCBs I should have by Friday of this week. Keep the suggestions coming...
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Joined: 11/10/2002 From: Mary Esther, Florida, FL, USA Status: offline
I did not give Jomar a point for having the box, nor did I take one from the BW for not having one. Had I not needed a place to mount the sockets I would have left the box off the Jomar.
With the BW production unit having the solder mask the score is adjusted, making it 17 to 1 in favor of the BW.
Anybody want the Jomar unit I showed? Nefer even been powered up, all the wiring and connectors are done except the sensor plugs - was waiting to cut the wires to length before soldering them on. Say "Please" and I'll do them too. Make an offer, with all the extra bits I have about $110 in it.
Bill.
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Real Airplanes have Two Engines AMA 25139 - More than 40 years.
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RE: Eletronic engine syncronizer - no joke - 
... here is a possible add on for you ... now that you have the RPM sensor in place ..how about a 
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