# Friday, September 26, 2008
So I have been getting into digital modes a lot more since HRD really has stepped up the cool factor. However I have a few issues with testing and playing. First I have no good antenna in my RF-Hell area to get out to any fellow nerds who have the time to play. Second I have no radio yet that is good for transmitting hours of testing.

I had a idea for the problem I have a stack of old FRS radios that I never use why not adapt the VOX of the Motorola FRS to the PC for use with HRD Digital Master 780

I set to work, first thing I learned was that the 2.5 mm jack that motrola uses is this weird "long jack" you can just hack up some cable for cell phone vox kits, I happen to have a texas instruments link cable from the old TI-85's I have sitting around. I have more then one so hack hack. I hacked up this particular cable because of two things 1. it had a nice ferrit coil so I eliminate (if any) RF into my sound card 2. you can hack away plastic and T.I. actually uses the long 2.5mm plug that motrola uses to make you buy their shit.

After some tinkering with the VOX I learned that you must short the MIC to get the radio to power up in VOX mode, however if you short it outright you get PTT mode. Simple fix throw in a resistor, I had a stack of 450kohm resistors sitting on my desk from a prior mess so used them. However I assume a 1k will work just fine.

Then just play simple hook up game, plug the radio speaker into the PC MICand radio MIC into PC speaker.

Simple little test shows it works, the volume is high but appears to not be clipping I havent scoped the audio yet to check but rather just went right to a test. hooked up two cables for two FRS radios. Turn on DM780 on two PC's and yup I have communication in CW. I havent tried any other modes yet but I would assume the only issue is the audio gain, DM780 will allow you to transmit at less then 0db gain right from the application, this is a setting to tinker with. Also volume on the radios I didnt fuss with (it was 2am with a working product I wanted to sleep)

Improvments might come from putting a cap in line or a POT to lower the input to the VOX on the radio, but I assume that I can fix all this in software with no need for additional hardware.

Next step is to heatshrink it all up and now I have a nice little demo kit for digital modes. I can also have some fun at any public space by transmitting oliva and watching people think its space creatures.

I have no idea if this is FCC legal, I couldnt find any data saying that you cant transmit digital modes on FRS bands. Seeing as its public domain frequency space I am also not very concerned with my transmissions since people also transmit music and swear there.

I used two Motrola T5420 FRS radios in this test. I also used 500k resistor


Update: I got some feedback in the legality of this - long boring legal document summerised: The most onerous restriction seems to be that the data transmission can't exceed one second, and there can't be more than one in a thirty-second period.

So if your super worried plug it into something else ... hell thinking about it you could just plug it right into another computer ...duh. But where is the fun in that? Legally you also cant swear on the FRS radios or CB radio so keep that in mind.
posted on Friday, September 26, 2008 9:48:08 AM (Pacific Daylight Time, UTC-07:00)  #    Comments [0] Trackback
# Friday, September 12, 2008

A common question I get is resources for the HAM hobby in the area. So here is a list of sites that I have found for Seattle and the pacnw.

Radio Reference – possibly the single greatest Internet database of law enforcement, and Public Frequency’s if you wonder what the light bar out side your house is talking about this is the location to get data. Also make sure to check out the forums there is a great location for learning and gathering data about how to scan or use radios.

Northwest Radio (Intercept Northwest) – Same Idea as the Radio Reference but specifically for the northwest, they have a lot more of the nitty gritty freq’ allocations like W hotel security, or McDonald's in Fife. forms to talk about local information

NWHam – here is a new kid on the block, this site is very slick. Has a repeater lookup database that is seemingly bad ass. Normally you must buy a book or do a lot of research for this data. This is a community fed database like RR.com to keep the data living. Again forms for HAM radio talk in the area.

I leave qrz.com for last because as its ‘the’ lookup database for amateur call signs. The forms are full of angry, know it all-Old farts that think that vista is cool because its new. Or google browser is great because its from ‘a real good company’ (translated to I wish my retirement was wrapped up in the google stock)

Other realms are the FCC ULS search which is the database for anything FCC (or everything).

HRO which is a suppler of radio equipment, the prices are not as good as they once were. but free shipping on over 100 bucks from Portland is normally good. Compare them to AES for best prices. Vetco is in Bellevue and has things if you need them now, but I very much dislike the staff there. (they also turned into the largest seller of HDTV crap ever)

Local Groups, Or Clubs are good if you’re into the group thing. The Mike and Key Club and the Puget Sound Repeater groups are good places to look into. There is a thousand groups in the area, from emergency to Boeing and Microsoft. Just Google search ‘Puget Sound Amateur Radio Club/Group’  to find more.

If you have uniden scanners check out the free tool bctool or freescan. Don’t buy the Butel Arc software its buggy and crappy for the price.

What to buy? Pages such as eham or RadioReference Wiki can help. The sites I have listed at the top all have Classifieds go there before you go to ebay. Craig’s list also always has mountains of crap. I find the local swap meets to be a waste of time for the most part. (Other then looking at other nerds) also check out groups.yahoo.com

Antenna’s …long topic, out is better then in. Big isn’t always the best. If it’s noisy get a tuned. Anything will work as good as the most expensive if you tinker. Noise blockers and RFI eliminators should be last resort.

Magazines, I find that the ARRL official mag is possibly the best. I am not an advocate of dumping money into ARRL but the subscription and online stuff you get is worth the cash. Popular Communications is also a great one to get. I have nothing good to say about Monitoring Times they don’t have good stuff on radios or the hobby IMO a lot of crap that PCMagazine also has. Sorry I don’t need a monthly grove catalog.

Books– the Northwest Frequency Database I carry with me everywhere I go. Official ARRL Repeater directory books are handy but sometimes are dated, However they are good to have. The ArtSci books are good, but also wrong or dated but you cant always have internet and they have sometimes better data then the ARRL.

Other things I would check out, is HamRadioDeluxe has a application for decoding digital modes, so far its the best I have found (including very $$$ apps) it will do most things that are still around.  MixW is a nice tool for some comparative analysis on digital modes as one solution won’t always work. It’s a pay for app with no development but you can use it with out paying. FlDigi is an open source app that you want on your tool belt as well expanding again some of the things you can do with digi-modes is another analyzer to use. If you want to try some fun the DigiPup bootable Linux distro will throw a lot of apps at you for testing.

Other applications that might be handy for tooling around the RF is TrueRTA for sound card digital analysis.  And unitrunker for trunk decoding,  PDW for decoding other commercial digital modes. GoogleEarth is also a good application to have handy, just don’t install the Google updater to keep the NSA from keeping its link to you updated.

You need to take a Radio Test? Look around, most people will do it for the cost of the license work (15 bucks or so) don’t pay a lot unless you want to support the cause. Email me and I can get you in touch with free study groups w/ test.

If you don’t have a radio or have no place for antennas check out EchoLink this will allow you to link your computer to a repeater to talk to stations all over the world, something you cant do as easy or reliably even with the most expensive radio.

And don’t tell people you have a GRMS license they will only snicker.

Hope this little blurb of information finds your Google search and that I can help.

posted on Friday, September 12, 2008 3:54:42 PM (Pacific Daylight Time, UTC-07:00)  #    Comments [0] Trackback
# Tuesday, April 03, 2007
I was browsing the FCC database today, the information in this database is insane. go look up a fcc ID today. Combined with the Patent Office search and you have all you need to hack things.
posted on Tuesday, April 03, 2007 11:33:27 AM (Pacific Daylight Time, UTC-07:00)  #    Comments [0] Trackback
# Wednesday, December 20, 2006
The ARRL is looking to drop all code for all FCC licenses. This is cool. Also about time who uses radios to communicate? The People Person of the year (me) they said blogs. Not Repeaters.
posted on Wednesday, December 20, 2006 9:19:01 AM (Pacific Standard Time, UTC-08:00)  #    Comments [0] Trackback
# Saturday, March 04, 2006
.... . .-. . / .. ... / .- / .. -. - . .-. . ... - .. -. --. / .-.. .. -. -.- / .. - / .-- .. .-.. .-.. / -.-. --- -. ...- . .-. - / -.-. --- -.. . / ..-. --- .-. / -.-- --- ..- .-.-.- / ... .. -. -.-. . / .-- . ... - . .-. . -. / ..- -. .. --- -. / ..-. .. -. .- .-.. .-.. -.-- / -... ..- - /- .... . / ... - --- .--. / - --- / - . .-.. . --. .-. .- -- ... / .. / - .... .. -. -.- / -.-- --- ..- / .- .-.. .-.. / ... .... --- ..- .-.. -.. / .-. . -- . -- -... . .-. / .-- .... .- - / - .... . / --. --- --- -.. / --- .-.. -.. / -.. .- -.-- ... / .. -. -.-. .-.. ..- -.. . -.. .-.-.- / ... - --- .--.
posted on Saturday, March 04, 2006 1:41:32 PM (Pacific Standard Time, UTC-08:00)  #    Comments [1] Trackback
# Monday, January 31, 2005

built me a pirate radio station – got a kit from here then hacked on it a bunch with some parts from vetco. Came out with this. I am having issue with the antenna so right now i can get about 2 blocks from home. I expect to be able to get 1 mile i just cant figure out my antenna stuff at the moment.

Fmtransmitter

The things i wanted to accomplish were setting the unit up in a portable box as well as getting more durable buttons for the menu system. To prolong life and keep it running happy i also wanted to get some active cooling in place to allow the transistors to keep nice and cool as well as the power amp. Mission accomplished now all i need is to get the transmitter transmitting at a solid 3w

posted on Monday, January 31, 2005 12:06:54 PM (Pacific Standard Time, UTC-08:00)  #    Comments [0] Trackback
# Friday, January 28, 2005

so yesterday we went on a field trip (pops and me) to Icom Radio we were looking at some display units in the corporate office when a guy was like “hey wanna see our ham shack” now this is possibly the most nerdy thing that you can ever say. But being that we were at Icom of all places you might as well take the time to look.

Icom

taken with my cell phone here is just a small snippet of the room. they have every production radio up and running in this room along with the elusive 7800 radio which i found out costs 10 grand! The guy didnt even know how to really use it, he played with a smaller version of it. Not bad for a days adventures, even if the nerd scale is off the charts.

posted on Friday, January 28, 2005 4:57:02 AM (Pacific Standard Time, UTC-08:00)  #    Comments [0] Trackback
# Sunday, January 16, 2005

gotta have the First Post

 

This is the new code for KellyKeeton.com/blog I chose to use the DasBlog asp.net source. with a work space here its nice easy setup just edit xml for the major options. I chose this because i wanted a ASP solution that would run on IIS and have no database back end. This was compared to .text which I didn't like as much.

posted on Sunday, January 16, 2005 10:23:04 AM (Pacific Standard Time, UTC-08:00)  #    Comments [2] Trackback