Sold / Found WTB: FM RX's

[Monkey Wrench]

Looking to buy a couple FM RX's. Ideally, Novak synthesized would be the way to go, but if I can get two that will work with an Airtronics/Sanwa MX-3, that'd be great. Should they HAPPEN to have channel 79 crystals, even better!

Willing to pay up to $50.00 each, depending on type and condition.

Thanks!

 

[Plaidfish]

can you use Futaba FM Rx's???
I have 2 of the small ones

 

[Monkey Wrench]

I might, but I guess I need to post a question in the Radio Gear forum. I'm having a hard time understanding why certain RX's are specified for a specific manufacturer? Maybe I'm an idiot (or "DINK" as Beason would say), but if I have a Sony radio and a RCA radio, they both will get 102.7 on the radio, right? I understand the crystals in the RX and TX must be the same, but otherwise, I don't get why the TX and RX need to be from the same maunfacturer, other than the style, size and shape of the wire leads going to them.

Plaid, if they work with either JR or Airtronics/Sanwa and are three channels, we've got a deal, man. I'll try to do some research on my end, but if you know, or anyone else looking at this, what's the difference, I'd appreciate it!

 

[beason]

hey man its not my fault that you missed the obvious solution.. (you know what i mean DINK!!)lol I've had the same question as i have a airtronics mx-3 that is in need of a few recievers. i would also like to know what is the difference, and what recievers are compatable with my tx.

I've already tried my hitech aggressor rx and it didnt work. both fm 75 mhz 3 ch

 

[Monkey Wrench]

Well Plaid, I guess this answers it:

The difference in FM RX's is that Futaba and Hitec work together and JR, Airtronics and KO work with each other. The reason for this is in the RX's they use phase shifting for transmitting and receiving. One company uses positive phase shifting and one uses negative so of course a positive will work with a positive and same with negative. Now this is only when it comes to 75Mhz FM. 27Mhz FM any manufacturer will work with any and the same with 75/27Mhz AM.

The reason they say to use matching crystals is the fact that they are matched from the factory to work together. Even though it says the same number between two manufacturers one could have a different tolerance and not be in total sync with the other crystal causing them not to work or have issues.

As for the Xxtra working with all radio's the reason for this is the first dial is set so 6-9 on the upper side will work with Hitec/Futaba and the 6-9 on the lower side will work with all the rest. If you have an airtronics and use the upper 6-9 you will find it won't work because the phase shifts aren't the same.


I appreciate it all the same, man!



Bump for anyone else?

 

[highflyin]

I have a Airtronics MX3S radio system.Comes with eveything that is listed on tower.The antena is slightly bent but is not really noticeable. It all works great.I have original box and manuals.I only used the radio and receiver so the servo,battery holder,and switch are new.I will take $70.00 shipped for it.Heres a link to what it is.
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXGRB0&P=7
Its great to not have to change crystals and not have to worry if the crystal is good.

 

[olds97_lss]

The novak xxtra does work just fine as a replacment or additional receiver for the mx-3. I have one in my revo now.

The only thing that kind of sucks is that the revo is setup for a xmitter with 50/50 on the throttle/brake channel. I don't think the MX-3 supports that. It's more of a 70/30 split instead. I reworked my linkages on my revo (significantly... PITA) to get it to work, but it works and works well.

 

[Monkey Wrench]

I appreciate it, Flyin, but I really am just looking for RX's at the moment. In reality, I need to thin my TX's out a bit. Thanks all the same!

 

[highflyin]

No problem.Good luck with your search.

 

[Monkey Wrench]

Olds, yeah the MX-3 is 70/30, but I've got a JR XR3i that I use in it. I'm trying to get to the point of only having one or two different TX crystals to worry about. I'm planning on using the MX-3 in my HPI MT and RC10GT.

I'd love to get the Novak's, but they're kind of high dollar new, but I may end up just breaking down and going that route.

 

[olds97_lss]

Well, the novaks are at tower right now for $65, which happens to be cheaper than the stock receivers that come with the MX-3.

 

[Monkey Wrench]

Yeah, just saw that myself! Thinking about it....

 

[jon2]

Hey dude I think I have my old R135 75MHz and maybe an extra Novak XXL 75MHz. P me if you are interested bro.