[Nashua Area Radio Society]

Ok FT8 is up and running and I am making contacts, however there is one small issue I am having. I am running in the Auto Seq mode and it seems to work fine, except it always skips the RRR on Tx4. I have looked through the manual and it doesn’t seem that have set something wrong. It happens on every contact, they send me a RRR and I send the a 73.

 

Any ideas?

 

 

[Nashua Area Radio Society]

I seem to have got it going, thank you for all of the input. I was watching it work and seems to stay in transmit mode for while, longer than I think it needs to. I am using a Signalink and appears to be working, but the transmit time concerns me. It this normal?

[Nashua Area Radio Society]

Which repeater are you folks using and when is this net scheduled please?

[Nashua Area Radio Society]

I can  only go down to 4800 baud on this Yaesu, tried but it didn’t make a difference. Still stumped

[Nashua Area Radio Society]

I have some useful information on the page linked below including the Rohn specs for tower installation.

http://www.richardcarter.net/radio/radio2.html

Rich – KE1EV

[Nashua Area Radio Society]

I was at HRO Salem today (10/30/2018) and very please to see plenty of N1FD QSLs with upcoming classes printed on the backside. GOOD JOB!

Layne AE1N

[Nashua Area Radio Society]

I will assume that your exploring your options with an Antenna modeling program such as EZnec before constructing the antenna. I’ll list a few generalized comments that may be helpful in understanding some of what your seeing.

1) VSWR is never constant across any Amateur BAND (e.g. 80/75M, 40M, etc.) for almost all antenna designs.  The HF band in question is 500 Khz wide with a center frequency of 3.75 Mhz (or about 13% of the center freq).

2) Height above ground will change the antenna’s impedance and resonant frequency (as well as radiation pattern).  Height is usually evaluated in wavelengths ( 1/8, 1/4, 3/8, 1/2…..  of the average antenna height).  The variations look like a dampened sinewave that eventually becomes a constant as you approach free space conditions.  This pattern is sometimes drawn as a spiral in the ARRL handbook and antenna books.

3) Standing Waves always result when the antenna’s impedance does NOT match the transmission line impedance.  An antenna matching unit can correct the SWR that the radio will “see”, BUT the standing waves still exist on the transmission line between the antenna and the ATU, so higher transmission line losses (increased heating) will be sustained in that line segment.  Note: These losses can be minimized by locating a REMOTE ATU as close to the antenna as is practical.

4) The heights described are an extremely small percentage of 1 wavelength, making this design a NVIS (Near Vertical Incident Skywave) antenna – aka a Cloud Burner.  The antenna pattern is largely almost straight up and the radiation pattern is almost OMNI-DIRECTIONAL.  E.G. there is a lot of radiation even along the end to end axis of the wire.  QST ran an article on NVIS antennas several years back and discussed how very low height antennas could serve very well during a natural disaster event where good LOCAL (200 mile radius) “omnidirectional” communication served best for reaching local responders.

5) The part of the antenna with the largest current flow will have the greatest effect on antenna performance (radiation angle and pattern)… usually getting this “as high as practical” is a good practice.   For a dipole, this the CENTER feed point.  Try supporting the center feed point higher up from a tree, tower or other available anchor point.  The ends can be lowered some and secured to some other lower anchor points (think of the inverted Vee antenna used for 40M on field day.  Lowering the ends of the dipole into the Vee shape will also provide a lower antenna feedpoint impedance and thus better VSWR results.

6) Trim the antenna for resonance around the frequency where you expect to operate the most… CW segment or Phone segment?  Make the best compromise possible during the adjustment phase.

7) Consider other antenna styles for your space: loops: delta loop; end fed L or sloper antennas.  Every situation is different and you’ll need to find a good on that works at your location.

Last:  Don’t be afraid to experiment – that how we all learn – and ANY ANTENNA is better than NO ANTENNA at all!  One this is almost certain: It won’t be the last piece of wire you ever put up.

I hope this helps answer some of your questions, and perhaps gives you a useful idea or two.

Mike

 

[Nashua Area Radio Society]

Also an excellent source for vintage test equipment manuals.

 

RB   K8EZB

[Nashua Area Radio Society]

Hello,

I was barely able to hear you guys last night when I tuned to the Westfield repeater. I’m over in Salem, NH. I was trying to connect to the Derry Repeater with the information provided and didn’t pick up anything.

I am able to connect to the Derry repeater that is listed at 146.850 and use it daily but could not find anything broadcasting on 146.730.

I will try again next week.

KC1KJQ

http://www.n1imo-n1imn.us/site.html

<b>Derry, NH </b>

This site serves as a secondary receive site for the 146.730 repeater.   This input to the system allows for mobiles to get into the system using a different PL or CTCSS.  To access the system, one would set their radio on 146.730 using a negative offset and a TX PL tone of 127.3. This site is located on Warner Hill at an elevation of 547′, and up 135′ on a tower.

[Nashua Area Radio Society]

For starters, go here for the 140 logging entries at DXZone. Each one has a point rating. Choose higher ratings to download an try. You should not have to pay for a good logging program.

https://www.dxzone.com/catalog/Software/Logging/

—Layne AE1N

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