[Repeater-Builder] Re: CTCSS Encoder/Decoder
For encoding, there's a million PIC-based solutions on the net. I designed my own, using a different PIC (12HV615) to reduce extra components to minimal: it has a built-in voltage stabilizer (no 78L05 needed, just a resisitor), and using bitstream D/A so no external D/A network neccessary. By bitstream D/A do you mean PWM? If so, how fast do you clock it how many serial bits do you use to create each sample? I use the hardware PWM generator inside the 12HV615. With 20 MHz clock I get 156 kHz cycles, with 7 bits resolution. Which is plenty: my main concern is to do noise-shaping, a simple RC filter filters out the high-frequency stuff (which is all around 156 kHz, i.e. several decades away from the desired low-frequency CTCSS tones). Again, don't worry much about the number of D/A bits; even a square wave only has odd harmonics. It is unfortunate that none of these low-pin PICs make the output of their internal D/A converter (CVref) available externally; it's only available as input to a comparator. I experimented with using the comparator as a buffer to get the D/A signal (putting a RC filter between output and inverting input of the comparator inside the PIC), this did work but somehow having a free-oscillating high-speed converter didn't seem very desirable from an EMC point of view. For decoder, check out http://www.mcarcoh.org/ke8rv/photo-sd.html, specific the comments about his controller. It's really mind-boggling what can be done with PICs. I see Don's using the analog input of a fairly low-end PIC, but I'd think you could use a digital input if the output of the LPF was limited via a very high gain amp. stage, a la ComSpec. Did he implement an IIR filter in the 12F675? He implemented Goerzel using fixed-point DSP. One issue has been detection time. I still need to find time to experiment with this myself. 73, Geert Jan
[Repeater-Builder] Decibel Z-Matcher Replacement Feed-Thru?
I have a sick Decibel DB4330 Z-Matcher with a crushed and mangled feed-thru capacitor (looks more like a ceramic non-capacitor feed-thru to me). Anyone know if the original feed-thru part is still available out there? Rough details: 10-32 x 3/8 body; 1 long 15 AWG wire ; ceramic insulator; 0.22 mounting hole; 5/16 flat hex-shaped outside end and a 10-32 nut inside the box. James K7ICU
Re: [Repeater-Builder] Re: 220 equipment
Bill, Give me a phone call about those 220 (217-219mhz) repeaters again. I would like to meet you in your area monday evening and drop those off. Thanks Norm N5NPO 251-234-0295 - Original Message - From: Repeater-Builder@yahoogroups.com Repeater-Builder@yahoogroups.com To: Repeater-Builder@yahoogroups.com Repeater-Builder@yahoogroups.com Sent: Wed May 05 17:36:08 2010 Subject: [Repeater-Builder] Re: 220 equipment They are useable for ham IF they are what I think you have described..The synth must be reverse engineered to get to ham freqs... I have begun this but not finished.we should talk offline... . bill --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , NORM KNAPP nkn...@... wrote: Tx is in the 217-219 range. I may end up with the 2 db228's as well. Are they usable for 220 ham? - Original Message - From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Wed May 05 08:50:06 2010 Subject: [Repeater-Builder] Re: 220 equipment Want to sell or donate them... they are FM and depending on if you have the base side or the boat side unit, it may be tx high or tx low. I am looking for the manuals for these units from the mid 1980's either the base or boat side. They were used on river boats mostly on the Mississippi River. Where are you located... . Bill Atlanta w4oo . . . . --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , NORM KNAPP nknapp@ wrote: I came across some 220mhz equipment and was wondering if it was good for anything... I got 3 Intech Incorporated COM 218 repeaters (?). Are these ACSB or are they FM? I also have some DB products circulators and a duplexer and a preselector TTA or something to that effect. 73... Norm
Re: [Repeater-Builder] Tait T800 S1 Eprom Problems
If you have the wrong reference oscillator selected, it will create steps that are invalid.. and thus syth unlock.. The ref osc for factory standalone units is based on 12.8 mhz but there is an optional 10.0 mhz ref osc.. and it can be external or internal. The PLL steps are calculated from that osc and the desired step size. You also need to select a channel in the channel switches that is occupied, it can be from 1-64 and the prom needs to be programmed accordingly.. Doug tait700 wrote: Hi, Was wondering if anyone had any knowledge or experience of any bugs when burning a new Eprom for one of the above units ? I can compose the new .Bin file correctly using PGM800 Win ( i think ) and send it to the Eprom burner that is telling me when it is finished that it is copied correctly to the chip ( via Verify ) but when the chip is installed on the eprom board and fitted to the tx module i have no VCO lock = no transmit. I have tried adjusting the VCO trimmer but cannot get it to lock with the new chip installed. I have added one other frequency to the original one that was on the original chip ( up exactly 10 mhz ) but it will not lock with either the original Channel freq or the new one on the new chip. The original Chip worked fine with the one that was on there and comparing the .bin file from this and the new one both look the same when opened with PGM800. I have read the previous posts on this board about creating a new eprom but if i have done something wrong i cannot see what it is. Any info or advice would be much appreciated, Unit in question is a T881 850 - 930 mhz Regards, Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: repeater-builder-dig...@yahoogroups.com repeater-builder-fullfeatu...@yahoogroups.com * To unsubscribe from this group, send an email to: repeater-builder-unsubscr...@yahoogroups.com * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: CTCSS Encoder/Decoder
I think this thread has clearly demonstrated that there are a couple different groups involved in building/maintaining repeaters. Those who are involved in commercial systems are likely best served by purchasing commercial grade parts/packages/systems, as their focus is on 'having' a repeater. Then there are those of us who are interested primarily in the experience of 'inventing /designing/ building/ debugging a repeater, and then starting over with a new idea. In behalf of all of us in this category, I say thank you all for your ideas, experiences and words of wisdom. As one who spent many years in the first group, I find it immeasurably enjoyable to now be one of the second group. No pressure to 'GET IT BACK ON THE AIR'. Just have some fun, learn something, and try to pass it on. VY 73 all, Wes AE6ZM VE7ELE ARRL Technical Specialist GROL/RADAR Lincoln, CA CM98iv --- In Repeater-Builder@yahoogroups.com, James Cicirello ka2...@... wrote: Thanks to all who have shared their comments and experience on the LM567 for CTCSS Encode and Decode. I have many ideas to work with now and in the future. You have all given me several ways to go from Skips comments on how to prefect the 567 to Ken and Jeff's recommendations on the CML Micro MX IC's. Again this group is the best resource for Amateur Radio Information available anywhere. Thanks to all who has taken the time to share information. 73 JIM KA2AJH Wellsville, NY
[Repeater-Builder] CTCSS Encoder/Decoder needed
Hey everyone, Look in your junkboxes, I 'm looking for an unmodified, working Com-Spec TE-64D Tone Box. cosmetics unimportant. Thanks de Lee K4LJP 73 -- Always drink upstream from the herd.
Re: [Repeater-Builder] Re: CTCSS Encoder/Decoder
And then there are those who need to 'have' a repeater but have next to no money and lots of time. As a member of that group I also appreciate discussions like this! I do the best I can with what I can get, and often end up spending untold hundreds of hours re-inventing the wheel. 73, Paul N1BUG ae6zm wrote: I think this thread has clearly demonstrated that there are a couple different groups involved in building/maintaining repeaters. Those who are involved in commercial systems are likely best served by purchasing commercial grade parts/packages/systems, as their focus is on 'having' a repeater. Then there are those of us who are interested primarily in the experience of 'inventing /designing/ building/ debugging a repeater, and then starting over with a new idea. In behalf of all of us in this category, I say thank you all for your ideas, experiences and words of wisdom. As one who spent many years in the first group, I find it immeasurably enjoyable to now be one of the second group. No pressure to 'GET IT BACK ON THE AIR'. Just have some fun, learn something, and try to pass it on.
[Repeater-Builder] Commercial VHF antenna on 2m
Hi folks, Several weeks ago I posed the question of using a Commercial VHF antenna that was resonant on 154Mhz on 146.745Mhz. We tried it today. The SWR was a bit over 2:1 on the repeater freq. We installed a T connector after the cans and used an open stub to try to match the line...got it down to 1.5:1, wouldn't go any lower. We think the height of the antenna makes up for what we suspect is a lot of loss in the antenna. The previous location of the repeater antenna was 100ft ASL and this location is 525ft ASL. Maybe one day we'll get a chance to retune the four dipole antenna. Thanks to all that provided ideas for this project. 73, dave wa3gin
Re: [Repeater-Builder] Re: CTCSS Encoder/Decoder
Amen to that! However, instead of re-inventing the wheel, I find myself spending a lot of time making discarded sow's ears into the proverbial silk purse. g 73 and aloha Eric KH6CQ --- On Sat, 5/8/10, N1BUG p...@n1bug.com wrote: From: N1BUG p...@n1bug.com Subject: Re: [Repeater-Builder] Re: CTCSS Encoder/Decoder To: Repeater-Builder@yahoogroups.com Date: Saturday, May 8, 2010, 5:19 PM And then there are those who need to 'have' a repeater but have next to no money and lots of time. As a member of that group I also appreciate discussions like this! I do the best I can with what I can get, and often end up spending untold hundreds of hours re-inventing the wheel. 73, Paul N1BUG ae6zm wrote: I think this thread has clearly demonstrated that there are a couple different groups involved in building/maintainin g repeaters. Those who are involved in commercial systems are likely best served by purchasing commercial grade parts/packages/ systems, as their focus is on 'having' a repeater. Then there are those of us who are interested primarily in the experience of 'inventing /designing/ building/ debugging a repeater, and then starting over with a new idea. In behalf of all of us in this category, I say thank you all for your ideas, experiences and words of wisdom. As one who spent many years in the first group, I find it immeasurably enjoyable to now be one of the second group. No pressure to 'GET IT BACK ON THE AIR'. Just have some fun, learn something, and try to pass it on.
[Repeater-Builder] Re: Different types of repeater people
ae6zm wesbfl...@... wrote: I think this thread has clearly demonstrated that there are a couple different groups involved in building/maintaining repeaters. Corecto' Those who are involved in commercial systems are likely best served by purchasing commercial grade parts/packages/systems, as their focus is on 'having' a repeater. Well everyone is best served with better quality gear... but it all comes down to how much and whose money is being spent. Then there are those of us who are interested primarily in the experience of 'inventing /designing/ building/ debugging a repeater, and then starting over with a new idea. Some of us are into self abuse... we try to make the original or first idea work. ... and like a pit bull dog it's hard to turn loose of that leg once you've bitten into it. In behalf of all of us in this category, I say thank you all for your ideas, experiences and words of wisdom. Always learning will keep you young... and sometimes crazy. As one who spent many years in the first group, I find it immeasurably enjoyable to now be one of the second group. It's a lot of fun to be on both groups... but any part of doing is fun regardless of what ever group you are in. No pressure to 'GET IT BACK ON THE AIR'. Just have some fun, learn something, and try to pass it on. No pressure? Do you realize how much heat a Ham Radio Club can generate when their Empire Building Repeater is off the air? VY 73 all, Wes AE6ZM VE7ELE Cheers, Wes, see you at the North Hills Swap the weekend after Dayton. Keep smiling, s.
