[Mich VHF UHF Society] June vhf -W8ISS en67

[jeffrey.wheelersr at gmail.com]

James, based on my experiences running MSK144 on 6 and 2 m, I’d like to offer some insight to the group who may not be familiar with it. MSK144 works very well for short burst meteor scatter propagation, especially on 6m. It also seems to work fairly well on E skip under some conditions.  Frequency stability and accuracy are very important when running digital programs at VHF and even more so at UHF.  On 6m, it is not uncommon to find stations running MSK144 +/-100 Hz of the center frequency of 1500 Hz. Occasionally some older rigs will be off as much as +/- 200 Hz.. Keeping the F Tol open to 200 Hz uses more computer resources and may adversely effect performance of some older or slower computers.  When you move you to 2m everything is multiplied by a factor of three, including Doppler shift and frequency accuracy.  Not everyone has a new radio with a GPS time base linked to the local oscillator. When I run 2m MSK144 I always keep the F Tol open to 200 Hz and there are times when I can “see” and/or hear a burst but it doesn’t decode. I suspect this is because the received signal is outside the F Tol of 200 Hz.. Duration of meteors on 2m is shorter compared to 6m as well. There is also an option to run MSK144 utilizing the SH or shorthand option. Simply check the SH box in MSK144.  This is used on 2m MSK144, allowing the software to use shorthand reporting information to take advantage of the shorter bursts associated with 2m.  I’m not sure anyone has tried MSK144 on 432Mhz. yet, but again everything will be three times more exaggerated from known 2m frequencies. The good thing is I seriously doubt there will be any useable meteors on 432 as the duration would be extremely short and Doppler extremely wide.  

For those who have never tried to work meteors, the best times are early morning from about 5 am to 10 am local and sometimes around midnight. As E skip is sporadic, keep your eyes and ears open. The stronger the E skip the less the need for MSK144, just pick up the microphone. You will probably discover running MSK144 that some stations adhere to an old tradition of East and West or first and third sequence depending on what direction you were aiming. This has become a bit of a controversy on the bands with some becoming very vocal if they believe you are “operating” on the wrong sequence.  For me I find keeping peace in my neighborhood works best.  If another local operator is running first sequence then I simply call CQ the same sequence and avoid any interference to each other regardless of whether I’m pointing East or West. That of course won’t work if you’re answering someone. Be patient with each other, try to cooperate by TXing the same sequences if possible and avoid the QRM problems. You can always move frequency and announce your activity on a Cluster and call CQ.  If you get “yelled at” on the air on a DX Cluster just take it in stride and remember its all just for fun.  None of us will become rich, famous or live longer if we win or loose a Ham Radio contest.  It is a neat mode, it eliminates call sign errors, language issues, grid square errors or time logged errors and saves your voice on this long contests. Logging is simple and can be imported to a contest logger like N1MM.  One final operating point with MSK144.  Please send 73 for a few sequences or until you receive a 73 back when completing a contact.  Don’t leave your QSO partner wondering if you received his RRR report by logging the QSO and moving on. Remember there is log checking and if I’m not sure you got my RRR, I may not log the QSO and we both get nicked. Good luck to all in the contest, I hope to work many of you from EN82.  

Best 73 Jeff W7JW
EN82 Michigan

From: James French 
Sent: Monday, June 05, 2017 4:26 PM
To: mivus at mivus.org 
Subject: [Mich VHF UHF Society] June vhf -W8ISS en67

I am planning to operate from EN67 this coming weekend. 

Will have 6m, 2m, and 70cm along with the 10ghz portable equipment.

Might get a late start on Saturday with the drive up to the Fort Wilkins state park from Lincoln Park  (en82jg). Starting out Friday night.

Will be trying out msk144 but no garunttees if I can get working on time. Mainly on 2m and 70cm.

James W8ISS




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