Getting back into RC questions

I've been out of RC for the past 5 years or so, but am making a comeback. I've got a few questions:

  1. I know that I will have to throw away all my old batteries. When I left the hobby 5 years ago Ni-Mh batteries were beginning to become more popular for RC. What is the status now.........Ni-Cds or Ni-Mh or something else.
  2. My radio equipment has been stored in a relatively dry area. Anything I need to do with transmitters, receivers, servos, before flying with them?
  3. Engines were run dry, and filled with Marvel Mystery Air Tool oil. Any recommendations before firing them up?

Thanks!

Reply to
Martin
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I've heard that Ni-Mh require special chargers and special handling. I'm sticking with Ni-cad for now.

New batteries, as you've already mentioned. Throughly cycle the servos and range-check completely before flying.

Empty the oil and rotate the crankshaft. Any grittiness is suspect for bearing rust.

Welcome back! Dr.1 Driver "There's a Hun in the sun!"

Reply to
Dr1Driver

I've used plenty of Ni-CD chargers of different types with Ni-Mh with no problems. If you want ultra high tech, then you want to look at Lithium Ion batteries. Those require special chargers to be safe. For high current drain applications (meaning certain electric motor applications), Ni-CD still has an edge.

--Brian

Reply to
Brian Gaither

-snip-

And ive wasted 2 RX packs in a row on their very first charge and also never got the third to fully charge using an MRC Superbrain charger that supposedly is Nimh compatable AND was setup correctly. My point is that i suspect you do really need a hi-end charger for NImh batts - or at least NOT the p.o.s. superbrain. Anybody wanna buy a charger?

Reply to
MikeF

Hello Martin

That's great, I've just had my comeback two years ago.

Ni-Cds for extreme usage and rough handling ....

Ni-Mh are now reliable power-sources up to medium currents. They need a suitable charger !!!

The newest is Li-Poly (Lithium Polymer), they work well in a low current (Parkflyer-like) setting and have a very high capacity to weight ratio but they are very, very sensitive and cannot be ultrafast recharged They are destroyed when decharged with high currents and cannot be decharged under the limit (3V/cell). Means they have a very small charge/decharge margin and need a charger which is able to charge Li-Poly. Last but not least, they are very expensive and have no over-pressure protection like NiCd and NiMh, means that they can literally "blow up" and cause harm (if not treated correctly ).

In generally I would highly recommend you to follow the indication on the battery especially about the way how to charge them (Very important in Li-Poly because they will become more dangerous than NiCd or NiMh, if you overcharge them), because there are big differences between the different types and brands. I usually use Sanyo 2000 RC, or 2400 RC NîCd or 3000 NiMh as propulsion battery.

I would recommend you to change the Frequency-quartz.

I can't give you any recommendations on this. I only fly electric..

Andreas

Reply to
Andreas Ebneter

Retired after 36 years in electronics, I'm still always open to learning something new. I don't understand the reason for recommending changing of the frequency xtals. I am not aware of any relationship between age and accuracy in crystals, except for flaking which can occur at any given time, new or old.

Phil AMA609

Reply to
pcoopy

Hello

This is a policy form some of my model-airplane friends. Personaly I think that it is not so much the duration of the storage, but more the duration of the use. But starting new after a longer break might be a good opportunity to change the xTals which had been just previously

Andreas

Reply to
Andreas Ebneter

Hello

This is a policy form some of my model-airplane friends. Personaly I think that it is not so much the duration of the storage, but more the duration of the use. But starting new after a longer break might be a good opportunity to change the xTals which had been just previously

Andreas

Reply to
Andreas Ebneter

I am still using crystals made in 1943 and they work great. What can you do to hurt a piece of rock other than break it?

Reply to
w4jle

How about putting it into a wooden box and shaking it vigorously by attaching a poorly-balanced 2 stroke engine and subjecting to occasional sudden violent decelerations? That's what I do to mine!

Reply to
David Smith

Might I suggest you go to a crystal manufactures site and take a look at the G-ratings specification.?

Proximity fuse ammunition during WW2 had miniature tubes (valves for my European friends) and crystals that survived being shot out of guns. Compare that with minute shaking of your two-stroke. Another example is the Sprint anti missile-missile. zero to five thousand mile an hour in under two seconds...

Changing crystals because it has set on a shelf is an unnecessary expense, the US Navy was firing WW2 ammunition, that had set on shelves, in exercises up to the time I got out in 1966.

Reply to
w4jle

My reply WAS supposed to be tongue in cheek! I recently subjected one of my Futaba rxs to a 'rapid deceleration test' that tore the rx case apart, just heard from the service agent that the xtal checked out fine, so I agree, they are pretty tough.

Reply to
David Smith

Actually, some of your Ni-Cd batteries may still be OK. Cycle them to find out. If they show less than 85% capacity, then discard them. Ni-Mh batteries can be charged using the same charger that came with your radio. No special charger is needed unless you wish to quick charge them. Of course, if the capacity is higher than the Ni-Cd you replace, you will have to charge for a proportionally longer time. I use the Ni-Mh batteries in my transmitters. The extra capacity is very nice when used with power hungry computer radios. Use in airborne packs isn't always a good idea. Ni-Cds still have the edge there.

Nope. Just check the batteries and do a normal range check.

Remove the glow plug, drain any excess oil and make sure the plug is dry. Use fresh fuel.

Jim - AMA 501383

Reply to
James D Jones

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