Getting Back into the Hobby

Well my wife really did it. She bought me a park flyer (FireFlight from the Sharper Image - similar to Hobbyzone's FireBird) and I'm having a blast. Now I've been eyeing all the old R/C stuff that hasn't flown in 10+ years. The first bird I'm likely to get back into the air is an old Great Planes PT-20 with an OS 0.25 engine. My old radio is one of Tower Hobbies old sets which I now understand makes a nice paperweight due to narrowbanding.

Therefore, I've recently bought off of Ebay a Tower Hobbies System 3k 4 channel transmitter. No servos, no receiver, no charger. I have a couple of questions that I'm sure someone here can help me with.

  1. Can I use my old Receiver, simply swapping the crystals ? I've tested this so far and aside from some channel assignments in the new transmitter, using the old Channel 44 non-narrow band crystal set, and everything seems to be working OK. Next test is to buy a 72 .990MHz crystal for the receiver and see if everything is OK. Anyone expect any problems ?

  1. Anyone got a charger set for this for sale ? Tower seems to sell them pretty cheap, but I thought I would check to see if someone had an extra.

Thanks

Todd Henry Please copy responses to snipped-for-privacy@bellsouth.net

Reply to
Todd Henry
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You _could_ use the old Rx, if you think you won't ever get 'hit' by RFI and there will never be anyone on the adjacent channels.

Worse, the old wide band Rxs were sometimes prone to 3IM products.

The new Rxs are also 'narrowband', and have a _lot_ better adjacent channel rejection, and third-order problems are unheard of these days.

Or at least, they're unreported these days maybe 'cuz new folks dunno what they are.

I'd pitch the whole wideband pile and start over; it's only money, right ? Cheers, Fred McClellan the dash plumber at mindspring dot com

Reply to
Fred McClellan

why not experiment with what you have to see how well it perform, you can make all sorts of tests, even with other pilots using near channels, if you make good testing before installing it, you can always deside if you want to use it later, why not.. it is free to test it !

Some of my old planes use original RX from 1980 to 1990 or so. they work even better compared to the new ones from 2003 !

Good luck ..have fun

Yours Thomas Scherrer OZ2CPU

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Reply to
Thomas Scherrer

Even though a wide band receiver is legal from a FCC standpoint, it may violate the AMA safety code. IF that matters to you.

Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email

Reply to
Dan Thompson

The simple answer is to just go out and start over with more recent technology. But you don't say what your invironment is (e.g, remote club field with good frequency management, or middle of city park with lot's of RF flying around) so you'll have to evaluate your own situation. If you will be flying at a club that's well away from city influence, then I'd say to go ahead and fly what you have as long as it meets the minumum requirements. As long as you keep in mind that you are at a greater risk of losing your aircraft and are prepared to accept that, then it's time to go fly.

Cheers, MJC

transmitter,

Reply to
MJC

| Now I've been eyeing all the old R/C stuff that hasn't flown in 10+ years. | The first bird I'm likely to get back into the air is an old Great Planes | PT-20 with an OS 0.25 engine. My old radio is one of Tower Hobbies old sets | which I now understand makes a nice paperweight due to narrowbanding.

Well, all radios made after 1991 are narrow band, and many radios made not too far before 1991 are too, so your equipment may be narrow band after all (I don't know how old it really is.) You might call up Tower Hobbies and make sure ...

Your batteries are almost certainly shot, but that's easy to replace. If you can solder batteries reasonably well (it does require some practice), you can buy 4 packs of 900 mAh NiCd cells from Wal-Mart or Home Depot for about $5 each and make your own. If you can't, spend the extra money and get some new batteries.

| Therefore, I've recently bought off of Ebay a Tower Hobbies System 3k 4 | channel transmitter. No servos, no receiver, no charger. I have a couple | of questions that I'm sure someone here can help me with. | | 1. Can I use my old Receiver, simply swapping the crystals ? I've tested | this so far and aside from some channel assignments in the new transmitter, | using the old Channel 44 non-narrow band crystal set, and everything seems | to be working OK.

If the old receiver is not narrow band, it'll pick up adjacent channel interference. It may also pick up interference from local pager towers. I'd suggest not using it for anything but testing stuff on the ground.

| Next test is to buy a 72 .990MHz crystal for the receiver | and see if everything is OK. Anyone expect any problems ?

Receivers are often tuned for a specific channel or range of channels. Outside of this range, you'll lose some range. But you're probably ok.

| 2. Anyone got a charger set for this for sale ? Tower seems to | sell them pretty cheap, but I thought I would check to see if | someone had an extra.

Don't you still have your old charger? It should still work.

If not, you're right -- they are pretty cheap --

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$10. $4 shipping.

Or you could get one used, as you're trying to do. They seem to accumulate after a while :) But at only $14, I'm not so sure it's even worth shipping one ...

Reply to
Doug McLaren

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