FT-950 Back On The Air

It's been a few months since I've fired up the FT-950. Got it dusted off and moved back to the shack. The last time it was used was at the MARG Field Day at the Long Island Marina in Kars. It's hard to forget how great the receiver is in the 950.

Late this afternoon I worked TK5IH in Corsica and ZP8AE in Paraguay, on PSK, with 589 and 599 reports using 20 watts to the Cushcraft R6000. Earlier in the day using the 'old' FT-100, I worked Maria, SA2YLM on 20 meters. 17 meters opened just after lunch for a short time and managed to snag a few Europeans with great 5NN reports.

The nice 'width' feature of the FT-950 allows me to narrow down the passband and get rid of high powered stations close to the DX that I want to work. The HRD* waterfall below shows the passband with many signals.



The HRD* waterfall below shows no signals, on either side of the received psk track. This eliminates desensing of the receiver by narrowing the passband so strong signals on either side of the track being decoded dissapear. The FT-950 can also notch out a signal on either side of the decoded signal.



I use Ham Radio Deluxe as control software and Digital Master 780 for digital modes. I find it is one of the most intuitive ham software suites. It keeps track of my logs and can be used for just about any digital mode now current on the amateur bands. There's an excellent satellite tracking module included. Simon Brown, HB9DRV, is continually adding features and tweaking the software. The Ham Radio Deluxe forums are a repository of information pertaining to any subject about digital modes and how to connect Yaesu, Icom, Kenwood, and just about any transceiver to sound card interfaces and to your shack computer. HRD works with Windows XP and Windows Vista.

Some PSK tips:

In PSK modes use UPPER CASE characters sparingly. Lower case text in PSK31 varicode transmits fewer bits of data. You'll increase transmit speed and improve the likelihood of proper decoding on the other end by using lower case text as much as possible. (For example, the difference between a lowercase “e” (11) and an uppercase “E” (1110111) is three times more bits.)

*Ham Radio Deluxe

Setting your radio for weak signal work

At VE3MPG digital modes are the preferred operating mode. I use low power and stealth type antennas and have been using PSK modes since I acquired my FT-100 in 2000. I ran across a really great article written by Larry, W7IUV, where he explains how to set up a FT2000 (or the FT-950 or any rig for that matter) for weak signal work and I'll quote some of his superb information below:

One of the biggest problems I see is that most people either don't know how to set up a radio for weak signal or they do and refuse to do it due to some personal agenda. Here's the way to hear weak signals either SSB, or CW;

Listen to the background noise. Does it move the S-meter at all? If yes you have the radio set up wrong. Yaesu provided a switch to select preamps or not and another switch to select input attenuation. USE THEM! On the low bands (160-30 meters) I will almost never operate with one of the preamps on. IPO ON all the time. Look at the S-meter. If it wiggles at all with background noise, add attenuation until it stops wiggling. On all modern radios there is about a 20-30dB difference between MDS and where the AGC starts working. You want the background noise (QRN, power line, QRM, whatever) to be at a level just below the point where the AGC starts working. That's also the point where the S-meter starts wiggling! At this level, when you tune across a weak signal it will jump up out of the noise at you. Note that setting the radio this way will NOT impair your ability to hear the weakest signal possible with current band conditions. The S-meter does not tell you S/N, stop trying to make it read upscale all the time!

Use the narrowest filter possible. Wide for me is 300 Hz. That's what I use for trolling the band. When things get tuff, I switch down as far as possible. Learn to use the narrow filters, they work far far better than screwing around with the shift and notch and other do-dads.

Do not use the RF gain control. If you have a SX-100 or a HQ-180 or maybe a R-390A it's a good thing. With modern radios like the FT-2000, using the IPO and ATT is far more effective. Also, depending on how and where the AGC voltage is applied to the RF and IF stages, using the RF gain control could possibly reduce your IMD performance and reduce you ability to hear weak signals due to increasing the noise figure faster than reducing the gain.

I've tried Larry's methods and on my 'old' FT100 it works great. On the FT-950 it works even better. I can copy weak psk signals better and it gets rid of much of the background noise. The signal traces on digital modes become very distinct using this method.

More info on Larry:

Larry - W7IUV
http://w7iuv.com/