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About drmarty

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    RC-Cam Visitor
  1. Terry, Technically, yes. See http://www.buchmann.ca/Chap4-page8.asp This is from Batteries in a Portable World. I wasn't trying to mislead anyone but merely to point out that 1) if your charger cuts off at 4.0 or 4.1 volts then the battery is not full and 2) if you see the battery going much past 4.25v I think you should stop it. Also they should not get hot. I think the Astro 109 probably uses the correct charging method but I wonder about the others. I have seen schematics for homemade chargers which clearly don't. Of course the Schulze ISL 6-330d (version 8) should be fine. Marty
  2. Oh yea, I forgot to add some things. Lithium cells are rated at 3.6 or 3.7 volts NOMINAL. That is a spec and a term that is worthless to us. Nominal doesn't even have a consistent definition. It is a design voltage or something. I am sure somebody will say it means something but for Lithium batteries it is of no help. Lithium batteries are charged at a constant voltage and a constant current and the charge is terminated by voltage and not an algorithm after "peaking." A lithium cell or pack is full when it has reached 4.2v per cell. That is 8.4v for a 2 cell pack and 12.6v for a 3 cell pack. Lithium cells should NEVER be taken below 3v per cell. The person that reported his Hobbico was cutting off at 7.4 or some such voltage should either check his charger or volt meter. If it is indeed stopping there it needs repaired. I think mine stopped at 8.2v or 8.3v hence my statement about not getting a full charge. These are not like Nicds where at the end of charge they are way over voltage and then settle down. There is very lilttle settling. If you notice your batteries are over 4.2v while charging, STOP. The Astro Flight 109 is reported to be a good charger (and Astro Flight has a good rep) and will do many cells and at high rates. The gold standard is the Schultze as someone mentioned. It is about $200 ($250 with the PC interface.) Can you tell I am lusting after one? I don't have enough chargers yet. Must Have. Must Have. (anybody want to buy a used _____ fill in the blank) just kidding. Marty
  3. I have MANY LiPo chargers. MAHA by Powerex, Triton from Great Planes, Hobbico field charger, 2 cell "chip charger" from Bob Selman, Apache 1 or 2 cell charger and Apache 1 to 4 cell Smart Charger. Hmm, Any more? MAHA $80 does up to 4 cells. max rate is 400ma for Li. No settings. As long as you have it on Li (instead of Ni) just plug it in and wait. It has a screen to let you know what is up. It charges for 3 minutes then analyzes and charges. I have charged a single cell 45 mAh up to a 12 cell 3S4P 4800 mAh pack without a problem. It does seem to over charge a little but the cells don't puff up and work great. My 3 cell packs (most of what I use) come out at 12.8 to 12.9v. Supposedly the biggest no no is overcharging but I use the MAHA for the bulk of my charging. It needs 24 v from its adapter to charge 3 or 4 cell Li. It can be used from a car battery for 1 or 2 cells. It has a temp probe but I wouldn't rely on it for Li. I got the Triton early and it is OK. They were cautious at first and it only charges about 90% full. The scuttlebutt is that the factory will fix this if you send it to them. It costs $130 and I think has a 2.5 amp upper rate. It has an optional temp probe but I think that is for Ni and by the time your Li triggered it you'd be screwed. It works from a car battery or power supply. "a field charger" Hobbico Field Charger is $50 and is actually 2 seperate chargers in one. It has no screen but does have separate banana jacks for a DVM which is cool. You don't pay for something you don't use but it is easy to work around. It has a max rate of 1 amp I think and also doesn't fully charge. It does about 95%. It also says it supports other cells but I wouldn't use it for NiMH. It will cook 'em. Runs on 12volts also. The 1-4 cell Apache is my new favorite. It is $55. It has a max rate of 2.5 amps which is good. it is easy to use. You set jumpers to tell it how many cells and the charge rate. At first I was put off by this as dangerous but note they call it a Smart Charger as it has protection circuits so if you set it to the wrong number of cells etc it won't charge and damage the batts. It is easy and fast. Is a small charger and runs off of up to 13.5 volts, ie a car battery. I have never used my Bob Selman charger. By the way as far as safety you hear all the warnings. OK, be careful. The charging of Li-ion, Li-polymer (or more accurately Li-ion-polymer hybrids) is the same. So if your charger like the Triton only says Li-ion it is OK. I would be glad to answer any questions. Marty
  4. The forum has been great help even in my dumbness so far. And now my latest problem. I found my first progammer was a Flash only and wouldn't work so I looked around and it seemed the Kitsrus K150 USB PIC Programmer would be fine. To speed things up I bought it assembled and tested and got the 40 pin ZIF socket for it. I am using a lab power supply for the necessary 16 volts DC so that shouldn't be a problem and when I power it up I get a power light on. I am having trouble getting my computer to recognize the board. I have all the latest software and the required drivers for the USB chip on the board (FTDI) I have reinstalled them several times and even restored my Win XP machine back to a clean status and reinstalled everything twice. When I plug or unplug the board my computer boinks like it knows a USB device is there. I have e-mailed Peter at Kitsrus and am eagerly awiting his response but I was hoping someone on this forum has used the K150 and may have some insight. Thanks, again. Getting closer (I think) Marty
  5. I try not to think about colonoscopy. Butt seriously. That camera is very big. It recieves the image through coherent fiberoptic bundles which actlike a long flexible lens. Sorry to burst that bubble. marty Dr. Marty
  6. well as I said your patience with us is profound. I ordered a bunch of stuff when I started this project and the chip came bare. It was in a piece of static foam wrapped in aluminum foil. No identifying info. I am not even sure why I think it is Richard's (tho I am sure it is now) anyhoo, onward and upward. boy am I red faced Marty
  7. I appreciate your patience. I used a programmed chip I got from Richard Ingram. I was careful with it but who knows? To check my connections I draw a picture of my hookup like I was getting ready to take it apart and then compare it to the instructions and it all looks right. pin 1 to the cap, the pos source and pin 5; pin 2 empty; pin 3 to shutter switch; pin 4 to res; pin 5 to pin 1; pin 6 empty; pin 7 empty; pin 8 to cap and ground. the Radio leads are Neg (brown) to USB housing, Pos (red) to USB the top pin; Signal (orange) to the res on pin 4. I rechecked the cap and res and they are the right values. .1microF and yel,viol,red, gold for a 4.7kohm 1/8 watt 5% tol. Voltages: 1) pin 8 to pin1 is +3.33vdc. 2) pin 4 is as follows (I started at the center then went both ways) 150 ms = 0.51v 100ms = 0.36v 200ms = 0.65v 70ms = 0.26v 230ms = 0.73v That looks good to me. 3) shorting pin 8 to 3 does in fact activate the shutter but of course that is chip independent (same as pushing shutter button) 4) checked and rechecked. I took a bunch of photos (all bad) Now I need to go find the manual for my digital camera so I can set it for macro - DUH. Will post photos maybe later. I have the programmer now but I didn't order the 40pin ZIF with it thinking I either didn't need it or could procure it locally. HaHa. the board has a 40 pin socket so there is no putting the 12C508 there and even though I live in Anaheim, CA and have many places to buy stuff - Orvac, Marvac, Action, Sav-on Electronics, as well as Fry's - nobody has the ZIF socket. I ordered it 2 days ago so we'll see. Then I only need to teach myself how to program the chips I have (10 of them) and VOILA I'll be up. Thanks for your patience. This must be a hoot watching people who probably shouldn't be trying this stuff try and do it. Marty
  8. Well I got the chip. Thanks. I installed it using Kynar wire. some of the soldering is interesting but all accomplished without a problem. Rechecked everything and reassembled. No worky. Opened it up and the wire from A to 3 had come off. Resoldered. Rechecked all others. Now when I plug in the camera to the receiver it beeps and the screen comes on. It will atake a picture with the shutter switch and the mode switch works. I get no response from the transmitter. I opened it up again and checked the voltages at the switch and at pin 3 and they are ok. I made a Y harness and put the camera with the throttle (I had it in the gear plug) and I checked the settings on the radio to assure complete "travel" Still no go. So, I unplugged the camera and put it in my servo tester which allows me to set the signal from 70 - 220 ms. Whe you turn it on it is at 150 ms which is the midpoint. Most systems consider 100 ms as low and 200 as high. I ran the signal down then up then back to the middle to arm it. I then tried to activate the shutter. No go. I then increased the range from 80 to 220 and then full range. (Maybe the upper limit is 230ms) Oh well, I know it will work. What can I test? I left the camera open and I have micro probes etc for my meter. I even have an oscilloscope (although I haven't used it much.) I am amazed at your patience as I read these pages and posts. Thanks for everything. Marty DrMarty MadMarty
  9. Thanks again for your prompt attention and quick help. marty
  10. RC Cam Man, Thanks for the reply. OK, I was up all night messing eith this and what you said is exactly what I was beginning to tumble to. It is wierd because they list the 12C508 as supported. OH well. Next step. Do I bundle this up and return it to Digikey? Or can I use a different 8 pin package with your hex code? Like the 12CXXX/JWND shich is an EPROM. Oh by the way, while I was reading the whole thread last night (and several others) I saw your offer to sell programmed chips. It was not until after I had e-mailed you that I saw the date was 2002. DUH. Sorry. I am helping a good friend with a college project and if I can get 1 working then I will probably make 4 more. I don't mind buying more chips if this programmer will work but I have read your site and it says it won't work as I read it. I can order the USB PIC programmer kitfor 35.95, or the P16PRO PIC Programmer for less than $20. Sorry to be so new at this but after reading and reading the pages it seems the difference is that the cheaper one is a parallel rather than USB device. Si o no? Thanks again.
  11. Well here I go. I have read and reread all the stuff. Thanks Mr RC Cam. I ordered the chips from Digikey. I ordered 10. I also ordered their Microchip PICkit 1 Flash starter kit programmer. It lists the 12C508 as being supported. When I try to write to the chip, I get an error. It says to "Insert Device." It does not appear to be writing but I don't know how to tell short of building it which seems like too much work since I am pretty sure it isn't working. Has anyone else used the Microchip PICkit 1 Flash Starter Kit? Help Thanks Marty
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