JR receiver help???
 

I just won this item from ebay
http://cgi.ebay.com/ws/eBayISAPI.dll...:X:RTQ:US:1123
and now I need to know which standard size receiver and micro receiver I need for this item.
Are these compatible for standard size?
http://www.ebay.com/itm/151157815443...84.m1438.l2649
http://www.ebay.com/itm/121208712618...84.m1438.l2649
http://www.ebay.com/itm/151160196401...84.m1438.l2649
http://www.ebay.com/itm/151160208406...84.m1438.l2649

I can not find any for micro size so any ideas? I would prefer to keep it in ebay and under $20 each.

ALSO, would I need specific servos or would any standard servo be compatible?

Thank you

The first Receiver you listed definitely will not work since it is a PCM receiver and that transmitter is FM only.

Also note that Tx is somewhat dated and has no model storage. What that means is you cannot program multiple airplanes in essence it is a 'one airplane one radio' system.

So any single conversion receiver will work as long as it is FM and 72 mhz???

Well not necessarily.....Your particular Transmitter is a Positive shift only Transmitter and that mean it will only function with a receiver which is Positive shift or is manually shift selectable or automatic shift selectable period. Nothing else will work.

OK now lets talk crystals since you cobbling a system together from EBay which is an extrodinarily bad idea especially if you do not already understand the many, many pitfalls of this abyss.

Since you cannot legally change Transmitter frequency crystals with a non module type radio which is what you have bought legally as well as morally if you need to change the Receiver crystal and that is fine understand you cannot just stick any old crystal in just because it matchs the frequency. If the receiver is a single conversion type receiver then you must have a single conversion crystal and if you have a dual conversion type receiver it must have a dual conversion type crystal. That is no guess the crystal type must match the conversion type of the Receiver.

Piecing a system together like you are doing unless you are an expert is a rocky road indeed.


John

Ok so I buy a single conversion positive shift JR receiver with a single conversion JR crystal and I am fine. The TX frequency is 21 by the way. I have bought TXs and RXs from ebay before with satisfactory results. Thank you for your help.

Yes that will work fine. Also there is a plethora of Hitec Receivers out there that were manufactured just for JR or airtronnics radios (both are positive shift) in positive shift and these will say right on the Hitec label JR in little tiny letters. Now there are also Hitec Recievers that are selectable for both positive and negative shifts and these will also work with your JR transmitter.

Lets talk about the dual/single conversion thing agine just for giggles. The Receiver conversion type has nothing to do with the positive negative shift thing That's a whole different issue. And the receivers conversion type has nothing to do with the transmitter so both dual and single conversion receivers can be used by you. The reason I brought it up is while not an issue for the transmitter but it is for the receiver crystal and that as I mention must be the appropriate crystal for the receiver.

Originally All JR receivers were single conversion and they used a slightly different filtering scenario that they called ABC&W Which you will see on some of those receivers. Later they went to dual conversion receivers and of course that requires a dual conversion crystal.


John

http://www.ebay.com/itm/151160196401...84.m1438.l2649
so this receiver will work fine then
and this one
http://www.ebay.com/itm/151160208406...84.m1438.l2649
on this one what does the PPM stand for?
http://www.ebay.com/itm/121208712618...84.m1438.l2649

Those should work. PPM stands for pulse position modulation which is considered FM. PCM or pulse code modulation is a different form of modulation and is not compatatble with PPM. For a more accurate explination you will need someone well versed in radio theory and something I am not.

John