November Engineering Report

Engineering report

Jesse Lindley K4AX

Well it’s November and almost the end of 2015, thinking back it’s been a interesting year serving on the GARA board and seeing some things get done that we have been wanting to do for a long time, such as a new website that can be accessed and updated by board members with a user’s forum for club members, the ability to renew and start membership from the website, planning and doing a G.A.R.A. run Field Day,  finally getting 501(c)(3) nonprofit tax status for G.A.R.A., and getting a new repeater ready to go online. I’m probably missing something, but it seems like we did a lot and I have enjoyed serving.

This month being time for our elections I hope we get to see you at the meeting voting, and as always we can always use people that want to run for board positions. I believe wholeheartedly that the same people should not be serving year after year on the board.  New ideas or different approaches to things can be good and bad, but you never know until it’s done.  Many times people don’t like how things are being done, serving on the board gets you into a place to have others see your ideas and make them happen.  If you can’t serve but are interested it would also be good to at least show up to board meetings and observe the process.

The VHF machine has not needed any attention recently, other than tweaking the preselector that had drifted out of alignment earlier this year that got us 10db of RX back, and losing power and reflashing the controller and DVR it’s been running smoothly. Still noisy at times, and that will probably get worse as the days get cooler with less humidity.  Also my last visit to the site I noticed that it seemed like mice may still be getting into the lower sections of the rack where the backup machine is located. Cleaning that out should probably be a monthly task.

The UHF Dstar machine has been running ok.  David tipped me off that the SSL cert had expired on the status and registration site @ https://w4gso.dstargateway.org/ and with his suggestion I get in contact with AA4RC whom is the author of the Dplus software who gave me the update script to get it squared away on the Linux Gateway computer. I noticed after checking a lot of reflectors and other gateways on repeaters it seems to be a common issue. On another note, also internet related, we have lost the internet connection out at the site twice in the last months’ time. Restarting the DSL modem and router seems to fix the issue.  I’d like to thank KK4VCG with helping me out with that the last time as I wasn’t able to get to the site during daytime hours due to work in a timely manner.

Last week Cameron and I finally were able to get our schedules aligned for a get together at his place to get the audio levels on the controller set to the correct deviation. We needed to set the levels on receive, transmit, the controllers audio, and the deviation of the CTCSS tone output. Everything was set to specifications/standards. Interesting process and it’s the first time that I think either of us has done it.  The tone output from this repeater will be different than what we currently have, it will be outputting a 100 Hz tone, the same as the input, which will help if you want to use squelch decoding, which is handy if you have a noisy environment or are mobile near a lot of leaky cable tv lines.  Currently tone output is at 67 Hz to negate a feedback issue with the current controller. As not many ham radios do a split tone, having both input and output tones the same will be a nice change.

One issue we noticed with the new Arcom controller and ADR interface is that there is a delay on the first keyup on the machine that will knock off the first letter of a call if someone is a “quick keyer”.  The ADR interface introduces a 100 millisecond delay to help with transitions between FM and Digital transmissions on the input. However we are seeing more than a 100ms delay, I’ve been in contact with the owner of Arcom to get the situation squared away.

We also have the new VHF amplifier on hand, it was picked up this week by Cameron. It is a Henry unit that is 100% duty cycle rated, and will put out 100 watts @ 20 watts drive. We will probably drive at less than 20 watts input. The current machine puts out 80 watts before it hits the duplexer if I remember correctly.

I hope to get the machine on the air very soon and as I’m tired of it taking up desk space in my shack and I want to use it from anywhere in town instead of my living room only and not having anyone to talk to on it.  As soon as I can work out knocking down the delay issue I’m putting it on the air. This week I actually have several days off in a row, and the first time I’ve had more than one day off in a week in a while.