Thread Tools
Dec 18, 2010, 05:21 PM
Registered User
Help!

Signal in FOCUS SS AM for FrSky 2.4G DIY


For probably very silly reasons, I would like to install a FrSky 2.4GHz DIY TX module in an old but functioning Hitec Focus 3 SS AM. With no buddy box option, it is not clear at first glance where to pick up the signal on the main circuit board (containing both the encoder and the RF broadcast electronics). I would greatly appreciate input from anyone familiar with these venerable radios who could direct me to the proper point to pull the signal. Many thanks for the bandwidth.
Sign up now
to remove ads between posts
Dec 18, 2010, 08:12 PM
Vi ne donu ĝin
coriolan's Avatar
Of course you realise the conversion will cost more than the Tx present value. If you have access to an oscilloscope its not too hard to trace were the ppm goes from the encoder to the RF part of the Tx. If you can post a picture of the inside of that transmitter it might even have a separate board fot the RF section since Focus were sold in many different bands for NA,Europe and Asia. Here is the manual if you don't have one:
http://www.hitecrcd.com/files/ManualFocus23AM.pdf
Last edited by coriolan; Dec 19, 2010 at 10:48 AM.
Dec 18, 2010, 10:35 PM
Inciting Riots
village_idiot's Avatar
The Focus FM version has a single circuit board with a single IC and several caps and tunable inductors. It appears the chip may have custom part number on it since I can't find a cross reference. I assume the AM version is the same.

As far as the PPM, I have no idea. I would suggest checking the pins on that single chip to see if there is PPM coming out of it.
Jun 16, 2011, 01:03 AM
Registered User
Mark Winstanley's Avatar
Quote:
Originally Posted by WERA611
For probably very silly reasons, I would like to install a FrSky 2.4GHz DIY TX module in an old but functioning Hitec Focus 3 SS AM. With no buddy box option, it is not clear at first glance where to pick up the signal on the main circuit board (containing both the encoder and the RF broadcast electronics). I would greatly appreciate input from anyone familiar with these venerable radios who could direct me to the proper point to pull the signal. Many thanks for the bandwidth.
WERA611; did you ever manage to convert your Focus 3 SS TX? I have one that I would like to do as well.

Mark.


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
For Sale Hitec Focus 2 SS AM Tx and HAS-03MB Rx PBR600RR Aircraft - General - Radio Equipment (FS/W) 2 Feb 18, 2011 01:51 AM
Wanted FrSky 2.4G 8-channel FUTABA FASST Receiver /TFR8 NIB unlvace Aircraft - General - Radio Equipment (FS/W) 0 Oct 03, 2010 07:43 PM
Sold Hitec Focus 2 ss AM Tx w/Rx and Ch 34 crystal --$20 shipped Tank52 Aircraft - General - Radio Equipment (FS/W) 5 Nov 04, 2005 12:59 AM
FS: Hitec Focus II SS AM 2 channel lv2soar Aircraft - General - Radio Equipment (FS/W) 4 Oct 18, 2004 06:20 PM