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LATEST NEWS: 23 September 2018

It's been over a year since I posted anything new to the BART. Seems like folks have lost interest in the site. KE5SQC - Randy has sent me material for the BART a couple of times and today, he sent a correction to text from back in 2015 or so. I've decided to start it up again and post the latest that we've been playing with, DMR (Digital Mobile Radio). Above is the Connect Systems CS-800D dual band digital remotely mounted control head that I've been using mobile. So, here's a few pictures.
	This Radioddity GD-77 dual band, DMR radio has been very popular with them selling in the $60 - $90 range. This was my first and I've had a lot of fun over the last year playing with it. We have two DMR repeaters in Tucson which are linked to 15 others in the Arizona/New Mexico area. You can find them on . So far locally, AB7IC - Tom, KB7YLU - Ted, N1DHS - Gary, N7KHZ - Bob, KB7ZZY - Jack, WA1BZQ - Bruce, KG7HHG - Bill, AG7LM - Bronze and N6YW - Billy have been active in the area. KE5SQC - Randy in Fishook and K7GEL - Ken in Sun Lakes are active too.
	It turns out that the repeaters, although digital and have two time slots for simultaneous conversations, are limited in the number of Talk Groups they are capable of having. MARC (Motorola Amateur Radio Club) set the standard of Digital (DMR) for amateur use, but in parallel with that came Brandmeister, a European group that was much more open and became the Wild West frontier of DMR, creating a system of a couple thousand Talk Groups. So, that led to the development of so-called Hot Spots such as the SharkRF Openspot shown left. Using it with the internet, it gives the capability for you to have your own personal access to all of the availible Talk Groups on Brandmeister. It is a low power, 20 mW, simplex transceiver you can use local or mobile as long as you can provide it with internet. Folks use cell phones and various tablet devices as internet hot-spots for mobile use.

I probably had the openspot two days when I thought "Wouldn't it be great to pipe the unit to an outside antenna?" So, I had been experimenting with using the dual band repeater antenna for 440 link radio use by plumbing an old Diawa diplexer and sharing the antenna. So, I hooked the SharkRF to the 440 side and was broadcasting in about a 5 mile radius and using it mobile around the East side. Then, I got my hands on an 8 Watt Digital amplifier and boosted it to several miles around Tucson.

The next idea I had was to interface the SharkRF Openspot to the repeater. So, I temporarily used one of the ports on the repeater controller and plugged in a GD-77 that I had modified to use as a link. I had to find a "Busy/Squelch Active" signal in the GD-77, so I opened it up and with N6YW's visual acuity, I had a signal tapped from the Green LED driver in the radio, swinging from 0 Volts squelched to 6 Volts squelch open. Then I hooked an 7808 regulator to the battery connections so I could use 13.8 V for the radio. it worked but is scheduled for future implementation.

As WB9TPD (SK) - Lee used to say, "Were having fun and that's what it's all about!

LATEST NEWS: 4 September 2021
WD8PDM - Frank sent me picures of a wood carving recently completed by his wife, KC8ODN - Denise. What do you think? Pretty good, huh!

LATEST NEWS: 20 August 2019
I guess it's official now. We have a BART DMR group, and KE5SQC - Randy has dubbed it the BART's FARTS, Three Ten Four Ten, One Step Beyond the Twilight Zone. We'll see how that works out. Future web page in working along with thee Gallery of BART's FARTS.