RE: Kraft Gold Spectrum 6
Here is what I did with one: http://www.rcuniverse.com/forum/m_10072737/anchors_10097051/mpage_1/key_/anchor/tm.htm#10097051 It works great on 2.4 gHz. The picture Jeff posted in the thread is mine. Pete
Posted on: 8/27/2012 1:53 PM by Author "modeltronics" in the forum "Golden Age, Vintage & Antique RC"
http://www.rcuniverse.com/forum/fb.asp?m=11208043

RE: Virus warning
If I got the screen shot in here....here is what I get:
Posted on: 8/27/2012 1:36 PM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=11208017

RE: Virus warning
I get it in the for sale section both at work and at home with McAfee. It totaly blocks me from looking at that section of the site.
Posted on: 8/27/2012 11:25 AM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=11207845

RE: Digital Servos + 2000mAh NiMH = Huh!?
3136 Yes, it might help if it can store enough energy for the current peak. If it does not then same old problem. Rodney If you see it flashing around and into the red then I agree, you have a problem. But if you do not see it flashing, you still might have a problem. Will a voltwatch react to a 100 milisecond voltage drop? And can your eyes even see it if it could react that fast. A voltwatch is just a stack of comparators similar to the LM3914. There is an upper and lower reference set on them to determine the range. http://www.ti.com/lit/ds/symlink/lm3914.pdf I will still hold that it does not give you enough information to be 100% safe. It is better than using nothing. Pete
Posted on: 6/21/2012 2:38 PM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11126921

RE: Digital Servos + 2000mAh NiMH = Huh!?
Tom Good point and I agree with you that it would be nice to see some specs published. I do have the equipment to make these measurments but don't have the time right now. It might make a good winter project to set this up on the bench to find the time and voltage to reset different receivers. Pete
Posted on: 6/21/2012 10:16 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11126693

RE: Digital Servos + 2000mAh NiMH = Huh!?
Hi Tom Take a voltage source and make it dip below the reset point of your receiver for 10 miliseconds (or even 100 miliseconds) while looking at it with a standard volt meter or a voltwatch. I can bet I know what you will see…nothing. I know what your receiver will see… a low enough voltage to reset it in some cases. Now look at it with a storage scope and you will see the voltage drop. Pete
Posted on: 6/21/2012 9:26 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11126605

RE: Digital Servos + 2000mAh NiMH = Huh!?
I’ve been reading this thread since it started and have made some comments in it. I would like to make a couple more but I do not want to start an argument. Using a voltwatch or a meter does not give you enough information. During the first less than 10 milliseconds that a servo starts to move there is a current inrush. The voltwatch or most meters are not fast enough to catch the current inrush and the voltage drop caused by the inrush. Even if they were fast enough your eyes would never catch it. It takes a storage scope to see this. ( and I know not everyone has a storage scope) Even though you cannot see this fast voltage drop it can be enough to brown out and reset your receiver. I did look at the voltmagic mentioned early in this thread and it is a much more useful device than a voltwatch. Also mentioned in this thread is a current meter. I would put that in the same case as using the voltwatch or voltmeter. It is just not fast enough to see what is going on. To see the peak current it takes a storage scope with a current probe. It is my opinion that some of the devices sold make you feel good but do not tell the entire story. Next is using NiMh batteries. The internal resistance of NiMh batteries is not a constant. It goes up as the current demand from them goes up. Be very careful when looking at the specifications of NiMh batteries. As the internal resistance goes up with the current draw so does the voltage drop. The internal resistance is not a linear function of current draw. I have worked in engineering with devices that use NiMh batteries and it took a lot of testing to find this out. This is just my 2 cents worth. Pete
Posted on: 6/21/2012 8:43 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11126543

RE: Digital Servos + 2000mAh NiMH = Huh!?
Tom, I just Googled Voltmagic. That is one very good device! There is a lot of good info on the FAQ page. I will be looking into getting one for my large plane. Thanks, Pete
Posted on: 6/9/2012 1:48 PM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11112524

RE: Digital Servos + 2000mAh NiMH = Huh!?
If you were to look at the voltage with the servos moving under load with a storage scope using NIMH batteries you might see something different than what a VOM of voltwatch shows. They are not fast enough to show what is realy going on. I know everyone does not have a storage scope. A VOM and voltwatch averages. Even if they were fast enough your eyes would never catch it. The inrush current of fast servos is enough to cause voltage drops and on top of that even though NIMH batteries have gotten better they still have higher internal resistance than other types of batteries. Pete
Posted on: 6/9/2012 9:44 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=11112365

RE: Kraft 2.4 ghz conversion help needed
Sorry to take so long to get back to you. I have been away from a computer for a few days. The way smallrc talks about should work very well. I did not have a zener diode so I used a regulated 5 volts on the collector of the NPN I used and inverted the signal at the same time. If I had to do it over again I think I could do it with a 741 op-amp to invert the PPM signal and limit it to 5 volts. On the Kraft Spectrum I pulled the module out. On the '74 Kraft it did not have a module and I just removed the crystal. Pete
Posted on: 1/31/2012 5:26 PM by Author "modeltronics" in the forum "Golden Age, Vintage & Antique RC"
http://www.rcuniverse.com/forum/fb.asp?m=10937571

RE: Kraft 2.4 ghz conversion help needed
Sorry. Some how I timed out on RCU and it double posted for me
Posted on: 1/31/2012 5:24 PM by Author "modeltronics" in the forum "Golden Age, Vintage & Antique RC"
http://www.rcuniverse.com/forum/fb.asp?m=10937570

RE: Kraft 2.4 ghz conversion help needed
I have done conversions on 2 Kraft radios. Please look at the info here. http://www.rcuniverse.com/forum/m_10072737/anchors_10097051/mpage_1/key_/anchor/tm.htm#10097051 I found that I had to modify the signal on the PPM line. The 2 radios I did the modulation went to almost the + battery voltage and the Frsky wants to see a modulation swing of 5 volts. Also I inverted the modulation signal before feeding into the Frsky module. This is simple to do and will only take a 5 volt regulator, an NPN transistor (2N2222) and a couple of resistors. I don't know for sure if you will have to do this. It worked for me. As far as finding the PPM modulation point, it is easy with a scope. I didn't tell you what you wanted but I hope this may help. Pete
Posted on: 1/25/2012 1:19 PM by Author "modeltronics" in the forum "Golden Age, Vintage & Antique RC"
http://www.rcuniverse.com/forum/fb.asp?m=10927053

RE: 4 Fried Hitec Servos in a Month
acerc, I am confused at what you are saying. You are telling me that when the servo is under load the voltage to it goes up? Also I don't understand "voltage draw" . Are you sure you are not talking about current?
Posted on: 1/19/2012 7:25 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10916875

RE: Have You Flown an RC Model Under the Influence of Alcohol?
I own a my private flying field and it has a place we spend the night in for long weekends. I will put up a glider on a hot summer day and sit in my chair flying it. I have had a beer next to me to sip on while flying. The problem I have is 45 minutes after finishing the beer and the glider is still floating in good summer thermals I need to get rid of that beer. try getting rid of that beer while flying....I've done it. Pete
Posted on: 12/16/2011 8:15 AM by Author "modeltronics" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10862282

RE: Alcohol and your AMA chartered flying club
One club I belonged to would let you have a beer after you were done flying. Once you opened the beer you were grounded for the rest of the evening. One guy had just opened a beer and had a sip sitting on the tailgate of his pick up when a new flyer yelled he was in having problems. This guy runs over and helps the new flyer. Some members of the club had a fit. I say he did the right thing. Another club I was a member of......If you were not holding a beer while you were not flying, someone would offer you one. As far as rules or having to drive home, here is my fix....... next year I am going to start building a house on my private flying field. Pete
Posted on: 12/13/2011 2:19 PM by Author "modeltronics" in the forum "AMA Discussions"
http://www.rcuniverse.com/forum/fb.asp?m=10857930

RE: Soldering Pencil help
I agree with Pettit. And I would put the MetCal at the top of the list. They are ready to use in less than one minute after power up. Pete
Posted on: 10/18/2011 6:56 AM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=10771051

RE: Pro Line (Electronics Inc.) - it's history?
If I remember right (correct me if I'm wrong) the pulse line going to a Pro Line servo is inverted to what all other brands use. If this is correct, why was this done? Pete
Posted on: 10/6/2011 9:19 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10751358

RE: Which is the better prop for an OS 26fs?
When I was flying one on an Ace 4-20 mine seemed happy with a Master Airscrew 9.5X6. It has been several years since I ran it so I can't give you any RPM numbers but it seemed like after trying several props that one was the prop that made the little 4-20 fly nice and sound good. I hope that helps. Pete
Posted on: 9/28/2011 1:20 PM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=10738812

RE: McCoy.35 Needle Valve Source ???
Here ya go: https://shop.mecoa.com/shopdisplayproducts.asp?id=102# mecoa has them for $7.60 Don't use modern fuel in that engine or it will only run once. You will need a fuel with lots of castor oil. Pete
Posted on: 9/7/2011 2:15 PM by Author "modeltronics" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10706079

RE: Do you still remember your first rc helicopter?which brand?
And a Lite Machine here too. It has a couple of dings but can still be put up in the air.
Posted on: 9/1/2011 1:36 PM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=10697106

RE: SHARE YOUR FrSky 2.4GHz EXPERIENCE !!!
I've put hack modules in two JR radios, one Airtronics, and one Kraft Spectrum6 http://www.rcuniverse.com/forum/m_10072737/tm.htm All work very well. Pete
Posted on: 9/1/2011 1:35 PM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10697103

RE: Servo chatter
EZ Fly OK, this gets me thinking it you have the same problem with 2 different servos. If you move those servos to another radio system does the problem follow? If the answer is no then I would begin to look at the radio. Could the pot on the stick of the transmitter be the problem? If you move the servo to another function on the radio does the problem follow? If you hold the stick on the TX in a different position does the servo chatter in the new fixed position? Do you have a scope? It would be interesting to look at the pulse width going to the servo to see if that is changing. And to look at the modulation line in the TX. I know most people do not have a scope. I'm just trying to look at this to see if the problem is in the servo or some other place in the system. I hope this helps, Pete EDIT I went back and re-read the first post, that you tried different transmitters and receivers. Next I would try plugging the servo directly into the receiver with the battery plugged into the receiver. This makes the most simple set up. If no chatter then put in the extentions. It could be as simple as the contacts on the extention being not quite good enough.
Posted on: 8/18/2011 8:38 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10675967

RE: Servo chatter
There is a pot in the servo that feeds back the position of the servo to the rest of the electronics. Since the servo spends a lot of its life near center that is the area that gets worn out first. The resistor material on the pot has only been silk screened on to the plastic base. The process is called thick film resistors. The screening process is similar to silk screening logos on t-shirts. So the feedback pots in servos are not the most robust. And on top of all this it has a wiper trying to rub through this pot material a lot near center. My guess is that the pot is showning some wear on the servo and the voltage at the wiper is not staying constant so the servo is moving around (chattering) trying to correct this. Pete
Posted on: 8/17/2011 2:19 PM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10674992

RE: Rossi Muffler - what is this?
There is another muffler that Rossi used that was all black. It looked very much like the mini-tuned muffler that MVVS used. That Rossi muffler was very loud. That is the one that I think jaka it talking about. I have used one that looked like the one shown in the original post. It was riveted together. I had problems with the rivets getting loose. Someone spot welded it for me and the problem was solved. Pete
Posted on: 8/17/2011 9:40 AM by Author "modeltronics" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10674595

RE: Rossi Muffler - what is this?
Someone can correct me if I am wrong but I think that is the Rossi quiet muffler. Pete
Posted on: 8/16/2011 9:21 AM by Author "modeltronics" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10673447

RE: Heating advice!
I have a shop about that size on some property I own near Abilene TX. I put in a propane wall heater. It looks like the heater that is on the wall in a hotel room. The heat stays in the shop but the exhaust goes out through a vent to the outside. I think mine is 25K BTU and heats the place just fine. I use upright propane tanks that are about 50 pounds. I bought 3 of them used in Juarez Mexico for about $15 each. They will heat the place for about a month each. If you want more information on them I will be there in a couple of weeks and can get the info off of the box. They are available in many different sizes. I have a 10K BTU heater still in the box that I am going to use for a sun room when we build a house up there. I bought them from a distributor in Dallas. Pete PS...I found the web site. Mine is the one at the bottom of the page. http://www.empirezoneheat.com/ehs/index.php?view=direct-vent-wall-furnace&parid=80&pagid=95&mlnid=80
Posted on: 7/25/2011 8:01 AM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=10637887

RE: Beware While ordering from HobbyKing
I have had one problem with Hobby King. I ordered a FrSky hack module and it was dead when I tried it. I have used several of these and never had a problem before. I contacted Hobby King and they told me to contact FrSky. FrSky said it should go back to Hobby King. So both places where pointing at the other as to where I should return it. I did notice that Hobby King was out of stock on these and that is my guess why they didn't want it back for an exchange. I tossed the dead one and ordered another from a place that had some in stock. I have a friend that returned a item that they say never got back to them. I have not placed many orders with them and try not to spend more than I can risk. I did get an item from them that I did not order, a 26X10 carbon fiber prop. I have no idea why they sent it to me and they did not want to pay the return shipping.....so I have a big prop as a gift. The question I have is, has anyone ever been to the Hobby King store in Hong Kong? I will be in Hong Kong this weekend and would be interested in stopping there. Pete
Posted on: 7/25/2011 7:48 AM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=10637775

RE: Brownouts....
Here is what works for me to see if there is a problem with the power to the receiver. (Note, I said works for me) I load the surfaces by hand to get a high current draw from the power source. At the same time I am watching the receiver voltage with a storage scope. (And I know not everyone has a scope). This will give you a lot more information than a volt-watch or a loaded voltage meter because they only give you an average of what is going on and are not fast enough to catch a quick voltage problem. A storage scope shows it all on what is going on with the supply and has saved me from having a problem. Some things I have learned are. Some regulators will dip in voltage and recover during a current spike. They are not quick enough to keep up with a high current inrush. I have also seen a voltage dip with some NiMh batteries. Both of these cannot be seen with a loaded meter looking at the battery because they are just not quick enough. Some servos have a very high inrush current as the motor in them just starts. I’ve only been able to see this with a scope. What I would like to know is how many mSec the voltage must be under the limit to get the receiver to reset. I know this is why some people put a 1000 uF cap on the receiver supply line in an unused servo channel. To me this only masks the problem of the power to the receiver. Again, I know that most people do not have a scope to check the set up of the supply in a model. I’m just passing on what I have learned. Pete
Posted on: 7/21/2011 6:54 AM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10631715

Solar Plane Paris air show
This is short but I thought it was interesting. A solar powered plane at the Paris Air Show. http://news.yahoo.com/video/science-15749654/new-solar-plane-can-fly-day-or-night-25771310.html#crsl=%252Fvideo%252Fscience-15749654%252Fnew-solar-plane-can-fly-day-or-night-25771310.html Pete
Posted on: 6/29/2011 2:39 PM by Author "modeltronics" in the forum "The Clubhouse"
http://www.rcuniverse.com/forum/fb.asp?m=10598709

RE: JR 50Mhz Rx. compatible W/ 53Mhz crystals ?
From the ARRL repeater directory. I only spent a minute online and found these so there might be a few more I missed. These are 10 khz from 53.1 the first RC channel on 53. I wonder how those 100 khz spaced receivers would work with a local repeater 10 khz away. Looks like the ARRL, that made the suggested band plan is publishing repeaters for people that do not like to follow the plan. Nothing is bullet proof. Oak Ridge 53.110 WD4GYN o WD4GYN Sevierville 53.090- KD4PBC ol PROP KD4PBC Waverly 53.090- NO4Q NO4Q Enough of this. I'm going flying :)
Posted on: 6/15/2011 2:05 PM by Author "modeltronics" in the forum "RC Radios, Transmitters, Receivers, Servos, gyros"
http://www.rcuniverse.com/forum/fb.asp?m=10575830