Date: Wed, 10 Aug 94 04:30:27 PDT From: Ham-Homebrew Mailing List and Newsgroup Errors-To: Ham-Homebrew-Errors@UCSD.Edu Reply-To: Ham-Homebrew@UCSD.Edu Precedence: Bulk Subject: Ham-Homebrew Digest V94 #229 To: Ham-Homebrew Ham-Homebrew Digest Wed, 10 Aug 94 Volume 94 : Issue 229 Today's Topics: cell sites Cyprus (ic Designs) Pll Chip, No External DSP for the HomeBrewer?? (part2) Freq standard from TV Colorburst subcarrier Handbook (2 msgs) Handheld and Saltwater... (2 msgs) HF preamp circuit - CORRECTION Need some help with the design of an Operational Amplifier Need TCM3105 ic New Life For Old FM Rigs (2 msgs) Ocean State Electronics Send Replies or notes for publication to: Send subscription requests to: Problems you can't solve otherwise to brian@ucsd.edu. Archives of past issues of the Ham-Homebrew Digest are available (by FTP only) from UCSD.Edu in directory "mailarchives/ham-homebrew". We trust that readers are intelligent enough to realize that all text herein consists of personal comments and does not represent the official policies or positions of any party. Your mileage may vary. So there. ---------------------------------------------------------------------- Date: 10 Aug 1994 02:30:11 GMT From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!vixen.cso.uiuc.edu!sdd.hp.com!hpscit.sc.hp.com!cupnews0.cup.hp.com!cupnews2.cup.hp.com!bmp@network.ucsd.edu Subject: cell sites To: ham-homebrew@ucsd.edu yctcsl@cerfnet.com wrote: : Does anyone have any info regarding the rate paid by PacBell (AirTouch) for : establishing a cell site lease. The offers been made however I'd be interested to : find out just what being paid these days. I'd negotiate for a phone or two with free airtime as part of the deal. Brian ------------------------------ Date: 09 Aug 94 17:07:00 -0500 From: blkcat!org!fidonet!z1!n109!f239!Timothy.Cadigan@uunet.uu.net Subject: Cyprus (ic Designs) Pll Chip, No External To: ham-homebrew@ucsd.edu Robert, I saw your note on pll chip on our local bbs, I would be interested in hearing if you have any luck with it. I've dabled with a few pll chips in the past. Having all the "stuff" done by the chip sounds great! Good luck and 73. Tim Cadigan, wc1f Timothy.Cadigan@f239.n109.z1.fidonet.org --------- Fidonet: Timothy Cadigan 1:109/239 Internet: Timothy.Cadigan@f239.n109.z1.fidonet.org ------------------------------ Date: Tue, 9 Aug 1994 15:38:31 GMT From: netcomsv!netcom.com!btoback@decwrl.dec.com Subject: DSP for the HomeBrewer?? (part2) To: ham-homebrew@ucsd.edu In article ahall@ux4.cso.uiuc.edu (Allen Hall) writes: >Hello again everyone, > >This is kinda an update to the question I first posed about homebrew DSP. >I have since my last posting recieved the chip that I had new was coming, >and I have some information that might help anyone who wants to make >suggestions to me. >... >-Please send me your suggestions on articles/books/ftpsites for any >information, or programs related to DSP. One book I've found particularly helpful is "Digital Signal Processing in Basic" published by Butterworth (!) and written by G.B. Lockhart and B.M.G. Cheetham. It covers Fourier transforms, filtering, and other things; it has both the math and the algorithms. An excellent introduction. -- Bruce KN6MN ------------------------------ Date: Tue, 09 Aug 1994 10:28 From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!gatech!newsxfer.itd.umich.edu!nntp.cs.ubc.ca!unixg.ubc.ca!news.mic.ucla.edu!MVS.OAC.UCLA.EDU!OSYSMAS@network.ucsd.edu Subject: Freq standard from TV Colorburst subcarrier To: ham-homebrew@ucsd.edu >Why would you want to use a TV station when there is WWV for free, and >it's more accurate?? You have it backwards -- the color carrier (when it worked), was more accurate. They were both based on atomic standards and the TV signal since it is local and VHF would have less noise than a HF WWV signal. Now however, with the widespread use of digital frame synchronizers you can no longer count on the color carrier being better than a normal crystal oscillator, with the possible exceptions of a few TV stations located at network sites (Los Angeles, New York?). Look into GPS (satellite microwave spread spectrum), LORAN-C (100 Khz pulse), or WWVB (60 Khz). >long wave on, I think it's 60KHz. Or if you're worried about the >atmospheric interference, there is also a way to call the NIST over land >line. And get variable phone line delays as well as freqency shifts.. ------------------------------ Date: 9 AUG 94 10:35:41 From: pa.dec.com!mrnews.mro.dec.com!est.enet.dec.com!randolph@decwrl.dec.com Subject: Handbook To: ham-homebrew@ucsd.edu In article <1994Aug8.235954.21300@knight.vf.ge.com>, hbrown@nadir.resd (Harry H. Brown) writes... >Tom, I can provide info on a 3 band solid state linear amp covering 6, 2 and >222 MHz and everything in between. > ... >Harry, W3IIT I wasn't so much looking for a project as lamenting the fact that no such is in the Handbook. It sounds great, though! Exactly the kind of project a lot of hams could use. I'd like to see less 1000W dummy loads and 2000W forced-air cooled amplifiers, and more 5W in, 50W out 2m amps, and easy to build test equipment to make sure your project is up to standards (some of that in there already). Also, some simple transistor rigs for the fun but little-used modes. The 6m CW/SSB rig in "Solid State Design" is a good example. Also like to see enough design info presented that the projects can be understood and adapted to other needs - the Handbook is already pretty good about the level of math included, just need more of it where appropriate. BTW, I have all the parts for that 2m amp in the '76 handbook - you can still get them. I'm gonna try putting it together soon. -Tom R. N1OOQ randolph@est.enet.dec.com ------------------------------ Date: 8 Aug 94 18:46:34 -0800 From: ihnp4.ucsd.edu!galaxy.ucr.edu!library.ucla.edu!csulb.edu!nic-nac.CSU.net!vax.sonoma.edu!harrisok@network.ucsd.edu Subject: Handbook To: ham-homebrew@ucsd.edu In article <1994Aug9.002019.21584@knight.vf.ge.com>, hbrown@nadir.resd (Harry H. Brown) writes: > > Tom, > I'm new to this and I think I may have screwed up the reply to the question > on dolif state amplifiers. In any case whoever is interested, the 6 meter, > 2 meter, and 222 MHz broadband amplifier has around 120 watts output linear. > > 73, > Harry, W3IIT Hi Harry... I'd be interested in info regarding this. I tried to send you email but it was returned. Please email me. 73, Ken -- ____________________________________________________________________ | Ken Harrison | I once thought I was wrong... | | N6MHG | | | harrisok@sonoma.edu | ...but I was mistaken. | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ------------------------------ Date: Mon, 8 Aug 1994 22:06:00 GMT From: newsflash.concordia.ca!pavo.concordia.ca!md_hill@uunet.uu.net Subject: Handheld and Saltwater... To: ham-homebrew@ucsd.edu In article <325rma$1g6@bigboote.WPI.EDU>, jmhill@duck.WPI.EDU (Jonathan M Hill) writes... >Hello all; > This is the first place I could think of to post just such a note, if >anyone can suggest another place I'd appreciate the pointer. > > Here is the problem I'm facing, I have a friend who managed to dip a >marine band handheld radio into the ocean for a short moment. Although the >moment was short, the radio was not immediately rinsed with fresh water, >thus some corrosion of parts must have taken place. > > I'd appreciate some advice, what kind of nasty business can saltwater >do to a radio? Anyone ever manage to dip a radio and manage to fix it >afterwards? The owner of this particular radio went back to the point of >sale, the sales person said in appoximate terms, "the radio is done for...." > > The radio is a Realistic MTX-120 VHF Marine Transceiver. The model >number is 19-1050, and serial number 05001434. I'd apprciate any pointers >to where I can find schematics, parts lists, allignment proceedures, but >especially troubleshooting and testing guidelines. I do have access to >suitable lab test gear. > > I'm just starting my adventure, so advice is welcomed. I noticed the >Uniden logo inside the radio cabinet. Thus, the radio must have been >manufactured for Realistic by Uniden. > > Thanks; > Water damaged equipment is often repairable. The most important thing is NOT TO TURN IT ON until you have had a chance to do the following: Open the radio. Take an old toothbrush and scrub the boards *carefuly* under luke-warm running water. In extreme cases, you might have to use a mild detergent (be careful that it doesn't eat anything). Of course, avoid getting water into anything like transformers etc. If there are components that are obviously too far gone, you will have to replace them; although if it was just a quick dunk, you are probably alright. Next, put the thing (minus the case) into the oven at about 60 deg. C and leave it for several hours. When it is cool, reassemble the unit but hook up a variable power supply in place of the batteries. Slowly bring up the voltage to the rated nominal voltage. NOW turn it on. If you were careful, meticulous, and somewhat lucky, the radio will be fine. Good luck 73 de VE2HVW ------------------------------ Date: 8 Aug 1994 17:57:30 GMT From: ihnp4.ucsd.edu!library.ucla.edu!agate!cat.cis.Brown.EDU!noc.near.net!bigboote.WPI.EDU!duck!jmhill@network.ucsd.edu Subject: Handheld and Saltwater... To: ham-homebrew@ucsd.edu Hello all; This is the first place I could think of to post just such a note, if anyone can suggest another place I'd appreciate the pointer. Here is the problem I'm facing, I have a friend who managed to dip a marine band handheld radio into the ocean for a short moment. Although the moment was short, the radio was not immediately rinsed with fresh water, thus some corrosion of parts must have taken place. I'd appreciate some advice, what kind of nasty business can saltwater do to a radio? Anyone ever manage to dip a radio and manage to fix it afterwards? The owner of this particular radio went back to the point of sale, the sales person said in appoximate terms, "the radio is done for...." The radio is a Realistic MTX-120 VHF Marine Transceiver. The model number is 19-1050, and serial number 05001434. I'd apprciate any pointers to where I can find schematics, parts lists, allignment proceedures, but especially troubleshooting and testing guidelines. I do have access to suitable lab test gear. I'm just starting my adventure, so advice is welcomed. I noticed the Uniden logo inside the radio cabinet. Thus, the radio must have been manufactured for Realistic by Uniden. Thanks; Jonathan Hill/N1QOL ------------------------------ Date: 9 Aug 94 16:19:47 GMT From: news-mail-gateway@ucsd.edu Subject: HF preamp circuit - CORRECTION To: ham-homebrew@ucsd.edu ACK!!! I forgot a resistor on the ubiquitous amplifier... Here it is (sigh...) again, less-incorrect... ****************************************************************************** V+ (12 volts) / \ |---------- | | / ----- 0.1 uf 0.01 330 ohms \ ----- / | |---||-----| \ __|___ | 3.3k | 470 ohms / / / / |--\/\/\/\-|-/\/\/\/----|__________________||___\ Output | / || / | B |/ C 0.1 uf Input>-||--|--------------------| 0.1uf | |\ | \ E / | Transistor: \ 1k / 2N5109 / \ 4.7 ohms (ECG278) \ / or use 2N2222 / \ (for HF, __|___ __|___ if you / / / / / / insist...) Note the 1k resistor to ground. It's kinda important, actually... Internet: clint@uugate.aim.utah.edu Amprnet: ka7oei@uugate.wa7slg.ampr.org ------------------------------ Date: 9 Aug 94 00:16:57 CDT From: ihnp4.ucsd.edu!ucsnews!sol.ctr.columbia.edu!howland.reston.ans.net!vixen.cso.uiuc.edu!newsfeed.ksu.ksu.edu!moe.ksu.ksu.edu!kuhub.cc.ukans.edu!christos@network.ucsd.edu Subject: Need some help with the design of an Operational Amplifier To: ham-homebrew@ucsd.edu hello there, I have a question concerning design of a simple amplifier using operational amplifiers. I am simply designing a noninverting amplifier with a gain of 2, that is R1=R2 ( Closed Loop Gain=(1+R2/R1) ). No matter what I apply to the input of the amp the output always saturates to -11 Volts. Even if no input is applied the output still gives a -11V. The voltages that I am applying to the Vcc+ and Vcc- of the op amp are +12V and -12V respectively. I am using the LM 741 opamp for this application. Does anybody in this group happen to know what the problem might be? I would appreciate any relevant response. Please e-mail. Thanks in advance Chris ------------------------------ Date: 10 Aug 94 01:30:43 GMT From: news-mail-gateway@ucsd.edu Subject: Need TCM3105 ic To: ham-homebrew@ucsd.edu I need a TCM3105 chip. This is a 16-pin 1200 bps half-duplex modem chip made by Texas Instruments. I need it to build the Poor Man's Packet interface. Does anyone know where this is available in single quantities? -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- ai351@leo.nmc.edu David Brodbeck Amateur packet (AX.25): N8SRE@wb4vva.#nemi.mi.usa.na -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- ------------------------------ Date: 8 Aug 94 19:25:49 GMT From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!usc!elroy.jpl.nasa.gov!netline-fddi.jpl.nasa.gov!nntp-server.caltech.edu!news.claremont.edu!bridge2!Thoth!peter@network.ucsd.edu Subject: New Life For Old FM Rigs To: ham-homebrew@ucsd.edu In article 7s7@netcom.com, btoback@netcom.com (Bruce Toback) writes: >In article greg@netcom.com (Greg Bullough) writes: >> >>It's a shame to retire my Drake UV-3 to packet service, now that virtually >>every local repeater requires PL tones. >> >>So I've been thinking about setting up an outboard sub-audible and DTMF >>encoder. Now the encoder and the DTMF pad are easy to obtain. However, >>most of the encoders seem to want a 5-bit encoding of values from 0-31 >>to select the sub-audible tones. > >Communication Specialists has an encoder that can be programmed with >a 31-position switch. You could also use a pair of hexadecimal thumbwheel >switches with a little translation table, or an EPROM with a switch that >contains just the PL frequencies you need. How much room do you have >for the controls? Is there enough room for hex switches, a rotary switch, >or whatever? How about using an 87xx series microcontroller and its timer output to generate a programmable frequency square wave? --- Peter Simpson, KA1AXY Peter_Simpson@3com.com 3Com Corporation (508) 836-1719 voice Northborough, MA 01532 (508) 393-6934 fax I speak only for myself, 3Com doesn't pay me to speak for them, so I don't. ------------------------------ Date: 5 Aug 94 14:36:03 GMT From: netcomsv!netcom.com!greg@decwrl.dec.com Subject: New Life For Old FM Rigs To: ham-homebrew@ucsd.edu It's a shame to retire my Drake UV-3 to packet service, now that virtually every local repeater requires PL tones. So I've been thinking about setting up an outboard sub-audible and DTMF encoder. Now the encoder and the DTMF pad are easy to obtain. However, most of the encoders seem to want a 5-bit encoding of values from 0-31 to select the sub-audible tones. The control circuits seem like a significant challenge. Does anyone know of a construction article or a kit for a sub-audible encoder with a human interface which is better than a row of dip switches? Greg ------------------------------ Date: 10 Aug 94 01:22:03 GMT From: news-mail-gateway@ucsd.edu Subject: Ocean State Electronics To: ham-homebrew@ucsd.edu Is Ocean State Electronics out of business? I haven't gotten a catalog from them in ages, and there's no answer at their 800 number. -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- ai351@leo.nmc.edu David Brodbeck Amateur packet (AX.25): N8SRE@wb4vva.#nemi.mi.usa.na -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- ------------------------------ Date: 9 Aug 1994 01:11:34 GMT From: nntp.crl.com!jeffj@decwrl.dec.com To: ham-homebrew@ucsd.edu References <7AUG199413272479@pavo.concordia.ca>, <776304324snz@arkas.demon.co.uk>, <8AUG199416550806@pavo.concordia.ca>cam. Subject : Re: NEC simulation software HILLIER, MARK D. (md_hill@pavo.concordia.ca) wrote: : > : >I did this, and was told by the machine that it was no longer anonymous ftp, : >and to go to ftp.netcom.com. This I also did; but, couldn't find any : >evidence of NEC files - there are literally zillions of directories under /pub, : >and nothing appeared obvious. Do you know if the anonymous ftp site still : >carries the NEC files, and if so, what directory path should I use to point me : >in the general direction of the ballpark? Look in a directory called randall, randal, rander something like that. Sorry this from memory and after a rough weekend is the best I can do right now. Jeff -- jeffj@crl.com | If work for a living and think the Republican party is your AB6MB | friend. Ask Republican congressmen if they ever would side | with labor over business. Then watch them laugh in your face! ------------------------------ End of Ham-Homebrew Digest V94 #229 ******************************