View Full Version : Must buy new TX module to change frequency?
3Dgonnabe
02-04-2005, 07:08 PM
Is this true? I went shopping for an new set of crystals today so I would have a different frequency to use in the event of a clash at fun flys. The LHS told me that it was illegal (in the US) to change the crystal in my RF module (9CHP). He also said I would lose range very badly.
Is this really the law?
If it is, why do Tower Hobbies sell pairs of crystals for 72 MHz transmitter and receivers?
Thanx!
DavidH
02-04-2005, 08:03 PM
Yes according to FCC regulations the crystal in the RF module should NOT be changed.
FCC CFR Title 47 Part 95 Subpart E Technical Regulations
Sec 95.645
(b) An R/C transmitter which incorporates plug-in frequency
determining modules which are changed by the user must be certificated
with the modules. Each module must contain all of the frequency
determining circuitry including the oscillator. Plug-in crystals are not
considered modules and must not be accessible to the user.
David
3Dgonnabe
02-04-2005, 09:38 PM
Cool! Thanks for the clarification, David.
Laurens
02-06-2005, 09:30 AM
You won't lose range while changing the crystal.
If it is, why do Tower Hobbies sell pairs of crystals for 72 MHz transmitter and receivers?
hopefully one of these days this (http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHKB1&P=ML)
will be released.
TH has postponed this thing since november.
TORNADOREX
02-28-2005, 12:55 AM
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHKB1&P=0
check this out it could help
NolanManley
02-28-2005, 11:15 AM
I'll be dang. Funny Futaba should finally come out with a synthesized module for the 9C. It's been shown for over a year but not available but the Hitec ones been around for 3 years. :lol:
They even matched the price. Finally! $89.99 :D
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXHKB1&P=ML
http://www2.gpmd.com/image/f/futl8910.jpg
http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXN550&P=ML
http://www.hitecrcd.com/Accesories/spectra72.jpg