Laurel Amateur Radio Club
The Feedback - January 1997


In this issue:

Sorry for all the JPEG files, I'm working to get the native text.

President's Ramblings

January 1997

Life is good - I have heat in the shack/garage, a Windows NT driver for my flatbed scanner, and the XYL has asked to takeover the household finances. Well, I guess two out of three ain't bad; and, hey, I am only a couple of months away from finishing my 1995 to-do list.

Yes, another year has again passed. It has been said that time is perceived to pass more quickly as one gets older and also that time flies when you're having fun. I like to think it is more of the latter, as I am sure all LARC members do.

I really think the club had another banner year in 1996. We once again carried out our full calendar of public service activities, added a few, managed to side the club house, win the MD/DC VHF QSO Party our first time out, get involved in emergency support with both the City of Laurel and the PG ARES/RACES organizations, did a bit of tailgating, and enjoyed another fantastic banquet at the Timbuktu (how did he do that?).

Many thanks go out to the officers, coordinators, and all the membership that supported the efforts of the club. Special kudos to Jim/WI3N and Pud/W3YD who have provided leadership, ambition, and vision to the club for the past 5 YEARS! They have been doing this stuff longer than I've had my license!

Somewhere in this issue you should find a current list of Club Officers and Coordinators, let me know if I have missed any. Many of the names have stayed the same - thank you in advance for your continued involvement. You will also find some opportunities (i.e., those activities with no names next to them) to get involved and take the reins of an activity or event. It would be wonderful if we could fill in the blanks in short order. Anybody have any suggestions for a build project?

Our biggest activity in the short-term is to get up to speed with our PG ARES and City of Laurel Emergency Preparedness roles. At our January meeting (this coming Wednesday on my calendar) we'll focus on those efforts. Jim/WI3N and Mike/WB3HUP will bring us up-to-date on those activities. I'm also hoping that Michele/WK3X will be giving an abbreviated version of her dog-n-pony show (no relation to Jim and Mike) that she so capably does for the Montgomery County RACES folks. PLEASE BRING ALONG ANY SHOW-N-TELL ITEMS THAT YOU THINK WOULD BE OF INTEREST (like your new gel cell battery, Dick).

Today, I got an email from HD/N3LFL with a web site to check out:

http://www.seas.gwu.edu/student/hanir/mdc/index.html

This is the ARRL Maryland/DC Section Page. If you get a chance you should take a gander at it. There is some good information there and I'm sure that I will refer to it often.

I guess I'm about ready to time out the repeater so I will say 73, hope to see you all soon…

Mark/N3NTQ


1997 Officers and Coordinators

Officers

PresidentMark Doore N3NTQmark.s.doore@bell-atl.com
Vice PresidentRoger Davis W3LMrldavis2@juno.com
SecretaryJohn Menard N3GXA
TreasurerPatty Menard N3OYN
FAR Rep #1Joe Seasley KA3UZI
FAR Rep #2Dan Blasberg KA8YPYdan.blasberg@mci.com
ARES/RACESMike Moseley WB3HUPwb3hup@aol.com
VECBob BuschWB3KXJ rbusch@erols.com
VEJohn CreelWB3GXW creewb3gxw@aol.com
Feedback EditorJohn Menard
(seeking replacement)
N3GXA
AutoCall ReporterJim Cross WI3Njcross3@juno.com
TrainingPud Reaver W3YDpreaver@erols.com
Immediate Past PresidentJim Cross WI3Njcross3@juno.com
T-MARC RepKevin Arber W3DADaa0005@mail.pratt.lib.md.us

Coordinators

Activity/Event TimeframeCoordinator
Training - General ClassJanuary (cancelled)
GW Birthday MarathonFebruary Pud/W3YD
Montpelier FestivalMay Roger/W3LM
Main Street FestivalMay Howard/K3IOG, Pud/W3YD
Laurel 5K Run/Walk JuneMark/N3NTQ
Field DayJune
Laurel 4th of JulyJuly
MD/DC QSO PartyAugust
Training - Novice/TechSeptember
FarFest TailgatingSeptember
Pallotti InvitationalSeptember
CROP WalkOctober
RiverfestOctober
SETOctober
JOTAOctober
SweepstakesNovember
Annual BanquetDecember
Laurel Christmas Tree LightingDecember
DC Roadrunners 10/20 MilerDecember



Kenwood TS-690S Transceiver
A Review

Kevin Arber, W3DAD

N3LFL, HD, brought a brand new TS-690S transceiver to the Club ARRL Sweepstakes effort. The operators used it during portions of the contest, and after the event was over, HD offered it to me to use for a few months for an evaluation.

The TS-690S is a TS-450S that includes six meters (50-54 MHz) which makes it an ideal rig for the technician plus operator. The TS-450S replaced the TS-440S in the Kenwood line. Since I have a TS-440S I was able to compare it to that rig as well. The TS-690S was preceded by the TS-680S; essentially a TS-440S with six meters. These rigs are available on the used market, normally at good value. Used TS-690S radios are in the $1200 price range. A used TS-440S or TS-680S goes for $600 - $800; List price for a new TS-690S is $1759.95 less options. TS-450S is being replaced in the Kenwood line by the TS-570D, a radio which incorporates DSP. As far as I know the TS-570D is not available with six meter coverage. List price for the TS-570D is $1819.95.

The N3LFL TS-690S is configured with an optional internal automatic antenna tuner (10-80 Meters), a TCXO and a 1.8KHz second IF (8830 KHz) filter.

I found this radio very easy to use with operation of most of the controls being intuitive. If you have used a TS-440S you will feel right at home with this radio. The radio has all the normal features; two vfos capable of split operation, 100 memories, all modes, RIT/XIT, IF shift, audio notch filter to name a few. The front panel is clearly marked and easy to read. The numbers on the push buttons contrast with the background making them easy to read, where the numbers on the TS-440S keypad are extreme ly difficult to see due to the lack of contrast. Operation on 40 Meters SSB produced reports of good audio quality from several stations using HD's Shure 444D microphone. The audio has punch as I was able to QSO a station in Port Huron, MI using only 10 Watts at 1947Z on 7204 KHz. By this time of the day 40 Meter skip is lengthening and the broadcast stations are getting strong.

On the bottom right of the front panel are four separate small controls labeled DELAY, CAR, PWR and MIC. DELAY sets the VOX delay to keep the transmitter keyed between speech syllables. It is set completely CCW for QSK operation in CW. The CAR (carrier level) control is used to adjust the carrier level during CW, AM, FM and FSK operation. The control is set completely CW for CW. PWR (power) is used to set the power output in all modes. The MIC (microphone gain) is adjusted during SSB by watching the A LC meter and during AM operations for 40W of carrier. Separating these controls, rather than having them as coaxial controls, is an improvement over the TS-440S/680S radios. The separate carrier and power controls allow complete control of the output from zero to full power (100 Watts)

Located on the upper right hand corner of the panel next to the display is a control marked M. CH/VFO CH. This control is used to change the frequency in 10 KHz steps (adjustable to 5, 2 or 1 KHz) permitting quick QSY over the band. This is a dangerous control! Turing this control changes the frequency up or down by 10 KHz and resets the VFO to zeros (rounds off) in the 1 , .1 and .01 KHz position of the frequency readout. If you are in the middle of a QSO and touch this control, you have lost your freq uency and getting back to it may take a while. Since it is located just above the RIT and to the left of the NOTCH control the mistake can be easily made. The round-off function can be disabled by programming during the power-up sequence, however, and I would recommend that you do so.

The radio has a number of firmware options that can be programmed during power-up. These include the linear keying relay ON/OFF. Changing this on the TS-440S involved removing the bottom cover and changing a switch. These are accessed by turning the radio on while holding down either the LSB/USB key or the M.IN key. The menu is numbered and is selected by the M.CH/VFO CH control. Functions are changed by the UP/DOWN switch.

The radio has options for several filter combinations. Filters can be installed at either the 8830 KHz second IF or 455 KHz third IF stage. A wide roofing filter follows the 73 MHz first IF (probably around 20KHz). The standard 8830 KHz filter is 6KHz wide. Optional filters are available for 2.4 or 1.8 KHz and 500 or 270 Hz. In the N3LFL radio the 1.8 KHz filter was installed. This IF also has a THRU (no filter) position for use with FM signals. The standard 455KHz filters are 12, 6 and 2.4KHz. The 455 KHz IF allows the use of one optional filter of either 500 or 250 Hz bandwidth. In operation I found the 1.8 KHz filter to be quite narrow and caused me difficulty in understanding speech. Tuning was also very unforgiving with the 1.8 KHz filter in use. As a result most of my operating was done with the 6 KHz filter in place. The 1.8 KHz filter may be useful in contest or under extremely crowded band conditions. Were I to purchase th radio I would install a 2.4 KHz and 500 KHz filter in the 8830 KHz IF and a 250 Hz filter in the 455 KHz IF. The 1.8 KHz filter was useful, however, during satellite operation (RS-10) on 10 Meters. While operating CW with the 1.8 KHz filter I found that I did not have to retune the receiver to follow a signal as it changed frequency due to doppler. The filters are extremely easy to change and do not involve soldering. The filter display is permanently labeled with the 2.4 KHz and 500 Hz markings, therefo re, if a 1.8 KHz or 270 Hz filter is installed the display wil l not reflect that. Operation is correct otherwise.

A nice feature of the radio is the automatic antenna tuner. I was able to load my wire antenna (200' inverted vee) on all bands except 17 meters where I could not get the SWR lower than 3:1. The radio requires that the carrier control be advanced slightly, about 1/8 to 1/4 turn to activate the tuner. Tuning was quick, reducing a 10:1 SWR (500 ohm resistor) to just over 1:1 in under 2 seconds. It was almost as quick in dealing with the complex impedance at the end of my inverted vee. The tuner uses cont inuously adjustable components rather than fixed components and relays and thus its operation is very quiet. I found this to be one of the radios most useful features.

The radio has an AIP (advanced intercept point) to improve its dynamic range characteristics. Turning AIP on did improve the radio's signal handling ability as tested on a DX CW pileup on 160 Meters . With AIP on, the RF amplifier located prior to the first fixer is removed from the circuit and resulted in a reduction in received signal strength of two to four S-units. The radio also has a 20dB attenuator that can be switched in to reduce noise and or intermodulation distortion. Since most transceivers today have excess gain at the low bands (30, 40, 80 and 160 Meters) the attenuator can be left in for low band operation. AIP off should be useful on the higher bands. The ARRL TS-450S review reported a third order intercept point of -33 dBm at 14 MHz , 500 Hz filter, AIP off. Turning AIP on should increase the intercept point by the gain of the amplifier, ARRL measured 11 dB, to -22 dBm. This is still not sterling performance. Adding the 20 dB attenuator would increase the IP3 to -2 dBm. By compariso n, the TS-440S tested by ARRL in December 1986 produced a IP3 of -5.5 dBm without the attenuator activated. The ARRL reported an IP3 of +9.6 dBm with preamp on for the new TS-570D in January 1997 QST and a whopping 21.7 dBm with the preamp off. That is sterling performance!

The radio features an audio notch filter which I found to be difficult to adjust. I did managed to get about 20 dB reduction in a heterodyne, which is what the specification calls out. I am probably spoiled after using a DSP notch filter for so long. Two noise blankers are provided. NB1 is for ignition type noise and NB2 is for longer duration pulses. Pushing the NB 1/2 key cycles the noise blankers cycles between NB1, NB2 and Off. NB2 can be programmed always off if desired.

The TS-690S & TS-450S provide provision for computer control. I tested this using the contest logging program CT. An interface between the computer is needed to convert the RS-232 voltage levels from the computer to TTL. Kenwood sells the IF-232C for this purpose; however, I used the home built interface that was constructed for use with my TS-440S. CT does not list the TS-450S in its receiver menu, so I called it a TS-940 and both CT and the TS-690S seemed happy. I limited my test to frequency selecti on, however, most of the functions can be controlled by a computer. Kenwood provides complete documentation for the control strings.

Overall I liked this radio and would recommend it for those interested in six meters and casual operation. If you are seriously considering obtaining a TS-690S, I would suggest you read the review in April 1992 QST for a full evaluation. Many thanks to HD for the loan of his transceiver.

NOTE: Since publication of this article in FEEDBACK, I noticed that Kenwood is now offering a TS-570S with 6 Meter coverage.


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Comments and suggestions may be sent to Mark Doore (N3NTQ).

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