To Synthesize or not to Synthesize - RC-Monster Forums

rustnpede · **To Synthesize or not to Synthesize -** 11.15.2006, 02:05 PM

Without much room to mount electronics, I was wondering how much interference you get with these monster motors, esc and Rx mounted so close together. I’m going to buy a new rx and tx for my bl revo and was debating on whether or not to get a synthesized setup. I don’t plan on racing so finding an open frequency isn’t a concern. Will a basic fm set up suffice?

coolhandcountry · 11.15.2006, 02:29 PM

I have had pretty good luck with just a single channel. I don't have no prob
with interference either.

nbcaznmaster · 11.15.2006, 06:33 PM

you oonly need 1 or 2 extra crystal sets just in case. but i only had to swap out my frequency once.

BrianG · 11.15.2006, 06:45 PM

Or, just get a Spektrum or Nomadio and not have to worry about crystals at all...

rustnpede · 11.16.2006, 03:20 AM

Im not woried about not having an available channel, just interference.

Happywing · 11.16.2006, 11:26 AM

Spektrum's a good deal right now. They have some new stuff coming out, so the old stuff's going cheap. You should be able to get a new DX2 with 2 servos for under $150.00. Sell the servos if you don't need them and the whole thing will end up costing a little over $100.00...And no interference.

JThiessen · 11.16.2006, 12:07 PM

SO what exactly does "synthesizing" mean? My new spektrum should be here in the next day or so, and I still dont completely understand the lingo.....

Also, what is the advantage of me upgrading my steering servo to a digital HT servo? They run about 100 bones, making me think twice about upgrading that part of the system.

Happywing · 11.16.2006, 11:54 PM

I think synthesized means you have a choice of all the channels, 61-90. With DSM (Spektrum) you have a channel that comes from a bank of thousands of channels. If someone happens to have the same channel as you, your system will automatically find an open channel...in milliseconds. As for the expensive servo. If you race, I think it's worth it. Digital servos center better and are a little faster. If you just bash, there are plenty of strong/fast anolog servos for a good price.

rustnpede · 11.17.2006, 04:42 PM

Quote:

Originally Posted by Happywing

Spektrum's a good deal right now. They have some new stuff coming out, so the old stuff's going cheap. You should be able to get a new DX2 with 2 servos for under $150.00. Sell the servos if you don't need them and the whole thing will end up costing a little over $100.00...And no interference.

Sounds good. I was considering a Synthesized Futaba 3PM-FS Pro ($180) but since interference isnt much of an issue I had decided on a futaba 2pl for $85. The DX2 is sort of in the middle so maybe Ill pick up one of thouse.

Just wondering, has anybody used an AM system with a highpower brushless setup? How much interference did that take in?

BrianG · 11.17.2006, 04:51 PM

I haven't used an AM system with BL, but I'd imagine it's not a good idea. AM modulates the servo signal on the tops and bottoms of the RF carrier signal, which is the exact place where noise would affect. FM is better since the frequency of the carrier signal shifts in proportion to the servo signals. The radio actually chops the tops and bottoms of the noisy carrier signal which makes FM much cleaner. Typically, both AM and FM are analog modulated. Digital is even better as there is usually error checking involved, not to mention the carrrier frequency is higher and out of the range of just about every noise making device on a BL setup (UBEC, motors, etc).