Re: [digitalradio] Need your help picking HF radio.
WRT the 857D DSP. Yes, it is at audio frequencies. (So is a sound card). Still quite helpful both in rejecting signals as close as 50 Hz (depending on mode) and lowering broadband noise. At present my 857D is on an older KAM+ TNC that does not have PSK but I have used the 857D's DSP to help with TNC PSK in a crowded band and there is no reason it should not help with sound-card modes. (My FT-450's audio DSP notch mode helps with MT63 and Olivia in the presence of broadcast carriers.) FWIW, I think the 857's optional filters are better than the 450's built-in IF DSP if only because you CAN use narrow filters in digital modes. The 450 only lets one go down to 1.8 KHz in digital mode which is not bad for MT-63 1 KHz or Olivia 1 KHz but not enough for the narrower modes. We are really spoiled by 10 Hz tuning steps. Sound cards can interpolate quite well. And even though the NTIA requires stability (IMO more important than frequency readout) of 10 Hz, that's over time and the manufacturers' rated temperature range. -10C to + 60C is NOT where I set the thermostat! Recent Amateur-grade rigs are enough after warm up in reasonably constant-temperature conditions and may not need a TCXO. I like them anyway.. Cortland KA5S [Original Message] From: Stelios Bounanos m0...@enotty.net To: digitalradio@yahoogroups.com Date: 12/26/2009 6:27:34 PM Subject: Re: [digitalradio] Need your help picking HF radio. On Fri, 25 Dec 2009 11:07:39 -0700, Alan Wilson ke4...@gmail.com said: I'd have to go with the Yaesu ft-857D, it does it all with a small footprint, reasonable price and very dependable... I have one of those and I like it for many reasons, but it's not a very good rig for digital modes. Some issues that come to mind: * DSP is at the audio stage, useless for digital. * Narrow IF filters (300 and 500 Hz) are extra. It can be frustrating to operate on HF without one of these. * TCXO is extra (but standard with the FT-897D, IIRC). * Minimum tuning step is 10Hz. * Much CAT functionality is undocumented by Yaesu, though HB9DRV and co. must have discovered all of it by now. * Reference oscillator is mounted behind the rear vent/heatsink and is therefore in the draft of air from the cooling fans. Fans always activate on transmit so you will drift, even for short transmissions and with the TCXO installed, which is most annoying on VHF/UHF. Can't blame Yaesu much about this though, it's a small rig. IMHO not worth considering for digital modes unless you _must_ have HF, 2m and 70cm in a compact radio. But then something like the IC-7000 is much better for that. And if you only want HF you have many more options. -- 73, Stelios, M0GLD. =is subject to: http://docs.yahoo.com/info/terms/
RE: [digitalradio] Need your help picking HF radio.
TS-480SAT for me, for QRP the IC-703. Simon Brown http://sdr-radio.com -Original Message- From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of Alan Wilson I'd have to go with the Yaesu ft-857D, it does it all with a small footprint, reasonable price and very dependable...73, es merry christmas...Alan
Re: [digitalradio] Need your help picking HF radio.
On Fri, 25 Dec 2009 11:07:39 -0700, Alan Wilson ke4...@gmail.com said: I'd have to go with the Yaesu ft-857D, it does it all with a small footprint, reasonable price and very dependable... I have one of those and I like it for many reasons, but it's not a very good rig for digital modes. Some issues that come to mind: * DSP is at the audio stage, useless for digital. * Narrow IF filters (300 and 500 Hz) are extra. It can be frustrating to operate on HF without one of these. * TCXO is extra (but standard with the FT-897D, IIRC). * Minimum tuning step is 10Hz. * Much CAT functionality is undocumented by Yaesu, though HB9DRV and co. must have discovered all of it by now. * Reference oscillator is mounted behind the rear vent/heatsink and is therefore in the draft of air from the cooling fans. Fans always activate on transmit so you will drift, even for short transmissions and with the TCXO installed, which is most annoying on VHF/UHF. Can't blame Yaesu much about this though, it's a small rig. IMHO not worth considering for digital modes unless you _must_ have HF, 2m and 70cm in a compact radio. But then something like the IC-7000 is much better for that. And if you only want HF you have many more options. -- 73, Stelios, M0GLD.
Re: [digitalradio] Need your help picking HF radio.
I don't know if it's the ultimate or not but I'm very happy with my nearly 1 year old Icom IC-7200. It is fairly compact and has IF level DSP. Probably the nicest digital mode feature though is the radio has it's own sound card circuitry. You connect from your computer to the USB port built into the radio and load the driver. After that the single USB connection carries all of the radio control commands (CIV) and the audio information to and from the rig. Leaves your computer's sound card available for other things. 73, Tim, N9PUZ
Re: [digitalradio] Need your help picking HF radio.
On Fri, 2009-12-25 at 15:46 +, kd7jeh wrote: Merry Christmas to the Group, I am looking to buy another HF radio for PSK/digital. I am asking what features I look for and why. Next question, what radio offers more bang for the money and why? I would like to buy new but will consider a used one of older model not in current production. Definitely consider one with a digital IF section. That gives you the maximum filtering possibilities without buying a bunch of filters. It's great when you can narrow your filter down to 50 hz and pick out a single PSK-31 stream. An added bonus is if the rigs AGC is derived after the digital filtering. I know the IC-746pro can do this and I'm sure there are many more that can, such as the IC-756proIII. It's a huge feature for digital work.
Re: [digitalradio] Need your help picking HF radio.
On Fri, Dec 25, 2009 at 11:07:39AM -0700, Alan Wilson wrote: I'd have to go with the Yaesu ft-857D, it does it all with a small footprint, reasonable price and very dependable. +1 Make sure it's the 857D, not the base FT-857; some of the base 857s have a problem with runaway oscillation on 6m, as I found out the hard way, but I've never had a problem with my 857D. If you get the optional all-in-1 hand mike, you can control everything on the radio except squelch level with the mike. The FT-857D works very well with Ham Radio Deluxe and with MixW, too. If you are willing to spend a bit more, you can get the FT-897D, bit brother to the FT-857D. The menu system is very similar, it can use that same all-in-1 hand mike, and you can run it through HRD and MixW, too. Both radios use the same programming software, too. Nice rigs. -- Mike Andrews, W5EGO mi...@mikea.ath.cx Tired old sysadmin
