What are the differences here?

Single conversion recievers have one image frequency.

Dual conversion has two stages of image frequencies and has better adjacent signal rejection.

The radio signal is converted down to a lower frequency for amplification.
the lesser one is 455khz I'm trying to remember the next one up but its somewhere around 1460khz.

The crystal in your reciever doesn't actually have a resonant frequency equal to the channel frequency, it differs by the image frequency.

Probably getting something started here?

Enjoy,

Jim

With respect to the beginners forum... one key point to get across is that you cannot tell from conversion alone which RX is better, i.e. more range, better Signal/Noise ratio, etc. On average, the dual conversion RX we can buy typically have better range and noise rejection than single conversion. This is becasue many single conversion RXs found in our hobby are intended for smaller models; HOWEVER, other single conversion RXs (such as a JR PCM RX, which I believe are single conversion) work just as good as any dual conversion RX (such as a Futaba PCM RX, which are dual conversion.) Cheers.

John did a good job of explaining some of the fallacies many have about dual versus single conversion; the biggest advantage of dual is the prevention of intermodulation distortion that can occur on some single conversion receivers. Each type has some advantages and dissadvantages the other does not have.

Ok......I understand that Dual Conversion is better or at least I have decided it is for me...lol
Now my problem is I have several TX units all
Dual Conversion with the appropriet crystals...........Several matching RX units all Dual Conversion with the appropriet Crystal.

My wonderful wife got me a 3D foamy with all the bells n whistles for Christmas with a Single Conversion RX.............see my prob? I don't have any Single Conversion RX crystals and I don't know if I can use this ultra light weight RX with my TX units such as the Eclipse 7.

Its a real nice Cirrus RX and the uses I would have for this with my future Foamy stuff would be most excellent to say the least but I don't know if I can use a Single conversion RX with Dual conversion TX..........anyone help with this?

Someone explained the diff between the two and compatibility or not .......several years ago...probably one of you guys. But I can't remember yesturdays breakfast, nevermind good info from 3 years ago. lol

You can use a single conversion reciever with a dual conversion transmitter.

The problem is that you need to know if the reciever is negative or positive shift?

I think the Hitec and Futaba are negative and the JR and Airtronics are positive.

I don't know what your receiver is but I do know you will have to get a crystal the same brand as your reciever.

http://hobbyoutlets.com/cirrus/446211.htm

Enjoy,

Jim

Thanks for your reply so quickly..........

The site says "automatic shift" maybe thats the pos/neg shift ?? Anyone else know about this?

I agree about the RX Crystal needs to be the same brand as the RX. I have heard that before and always try to do that.

I am thankfull that the single conversion can be used with a Dual conversion at least.

Auto shift means that it will run with either kind of transmitter

Ahhhh

Either being Positive or Neg shift........got it.
Thanks

Also, the transmitter is not single or dual conversion, just think of it as a transmitter. As W8YE stated, you will have to worry about positive or negative shift coming out of the transmitter that the receiver must match. Also you have PPM or PCM as a transmission type. Any transmitter that can operate as PCM can be set to transmit in PPM mode. Most lower end transmitters are PPM only. Just something else to think about when buying a receiver.

Also, all JR single conversion receivers, both PPm and PCM can go toe to toe with the other manufacturers dual conversion receivers. Dual conversion is not the only method that does a good job.

Ed M.

Thanks to all

With what little I know.......and what dribbles off onto the wife...........we might be able to keep from blowing ourselfs up. lol

Its hard to remember everything all the time and somthing I asks and got several years ago....don't mean I remember it today....or tomorrow........or........in fifteen minutes. lol