Choosing a radio for remote operation

Recently I had an email exchange about the relative merits of a Kenwood TS-B2000 or a FlexRadio transceiver as a choice for a remote station… after a couple more emails, I thought I'd publish the thoughts below…

YMMV!

Comparing the Kenwood TS-B2000 and FlexRadio

TS-B2000 versus F3K (never used a 3K, but VERY happy owner of a 5K)

• TS2K has support for HF thru 440 MHz – very flexible, all modes
• F3K – HF thru 6m
• Haven't operated F3K but similar to the F5K in performance.  RX is very good, very much better RX than TS2K, I've worked and heard stations especially on 160m that weren't even audible on the TS-B2K.
• Filter capabilities of Flex are much superior to TS2K – not much of an issue in normal operation but in contest, no comparison – the Flex is the winner by far.
• Flex has better computer control with PowerSDR – ALL controls are accessible and very easy to access.  Situation with TS2K is ok and usable – not so straight forward and different control programs offer different (and all incomplete) solutions. 
• TS2K has more antenna switching capability than F3K – depending on the antennas you will use at remote location; you may need external antenna switching with the F3K.  TS2K has 4 antenna options – 2 for HF/6m, one for 2m, one for 440.  These are selectable via the CAT programs or automatic in the case of 2m/440. The Flex 5K has the best switching I've seen built into a transceiver.

 

Remote Operation options

• Everything over Internet;
  • use UltraVNC or similar for computer control
  • Skype (make sure latest version at both ends) for audio.  Bandwidth requirements for audio are minimal.
  • Bandwidth requirement depends on refresh rate of video image – can control this with PowerSDR by setting Panadaptor refresh rate to small number.  Still usable with refresh rate about 2-4/second.  Cuts bandwidth requirement dramatically.  In this configuration, I've operated successfully over hotel class broadband links with 2-3 Mbps of bandwidth down.  Upstream is small – only a few 10s of Kbps.  In my home setup where I have 1 G Ethernet around the house, the full bandwidth from the remote station PC is about 20 Mbps – this is with high frame rate in PowerSDR (15 frames/second) and full Waterfall displays going.  < 2% of LAN bandwidth – PC runs it very easily!
  • Use digitial software like MTTY that has smaller digital display (no waterfall or very small)
  • CW operation using built in keyer in either PSDR or TS2K – haven't tried WinKey at both ends (you can run 2 WinKey units back to back over the Internet to use a physical key) – might work.
  • VAC provides virtual sounds card to allow flexible audio routing – with F3K solution, won't require external audio cables.  External cables needed for the TS2K.
  • Skype imposes some latency – depends on number of relay links – depending on your Internet configuration, you may not see any relays even over long distances (for example, over Christmas Holiday, I operated from Colorado back to California – no Skype relays).  Depending on audio latency, you may find contest operation impossible and attempting to crack a DX pileup very difficult.  Very usable for casual QSOs.
• Control over Internet, audio over telephone
  • You can use a telephone line to connect the audio – I've run this configuration too in fact for many years with my TSB2K over a private phone line via the small PBX in our house.  Works very well!  Adds about $500 to the cost for the two telephone couplers.  I can point you at suppliers of the auto answer coupler – these are still used by radio stations for call in lines and single line versions are about $250.  MFJ makes a phone patch that with some modification you can use to drive a remote setup – I did the modifications on one of the MFJ units – took me about 2 hours (need to add an audio amplifier so that the Mic can drive the phone line).
  • This gives a very low latency solution – contests and DX pileups are now a matter of operator capabilities, not system capabilities!
  • You need remote control via the PC in order to be able to hang up the telephone line via a relay closure – this requires some simple external hardware at the PC end.
  • You don't need a dedicated line to do this – a regular dialup line works fine.

 

In my current home system, I replaced the telephone line with a home brew audio link that drives balanced audio over a spare LAN cable.  I use the 4 pairs in the cable to give me stereo audio from the Flex (2 channels), mic and PTT back to the Flex.  Works very well and since its analog, zero latency (well, almost!).

The TS2K is a reasonable radio – the Flex is a GREAT radio.  Far superior in my opinion and very much easier to integrate into a remote station – its possible that my view on this is a result of the experience (frustrations and solved problems!) over the years of building and operating a remote station.  We moved to this location in 2003 and I've operated 100% remote ever since – a lot of miles of operation so to speak!