Date: Mon, 25 Apr 94 04:30:29 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 #110 To: Ham-Homebrew Ham-Homebrew Digest Mon, 25 Apr 94 Volume 94 : Issue 110 Today's Topics: 40 meter CW transceiver project? PSK Modem QRP neswwsgroup (2 msgs) R2 T2 pcb source wanted TI 320C26 DSP Eval Kit TUBE WANTED: CK-1905 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: 24 Apr 1994 13:59:04 -0400 From: ihnp4.ucsd.edu!library.ucla.edu!europa.eng.gtefsd.com!news.ans.net!hp81.prod.aol.net!search01.news.aol.com!not-for-mail@network.ucsd.edu Subject: 40 meter CW transceiver project? To: ham-homebrew@ucsd.edu In article <1994Apr22.122214.62719@kuhub.cc.ukans.edu>, mmarmor@kuhub.cc.ukans.edu writes: >Can anyone recommend a good "builder in training" 40 meter CW >transceiver design? Will I be unhappy with the performance of >this type of no frills rig? (It won't be any fun if I can't make >a few contacts using it!) I can only address what little experience I've had--starting with QRP. Try a simple design using a crystal for the frequency generation, rather than a VFO (to keep it simple). Shoot for 1-2 watts output. Once you're happy with that (and you will make contacts with it), you might try converting the oscillator to a VXO nd adding some more power with a PA up to say, 3-5 watts. I've taken this approach and been quite surprised with the contacts I've made, especially on 30 and 40 meters. Let me know how you fare! 73 de JimN0OCT ENTROPY AINT WHAT IT USED TO BE! ------------------------------ Date: 25 Apr 94 18:41:24 NZST From: waikato!comp.vuw.ac.nz!newshost.wcc.govt.nz!kosmos.wcc.govt.nz!parnell_j@decwrl.dec.com Subject: PSK Modem To: ham-homebrew@ucsd.edu I would like to revisit the thread on how to do PSK demodulation that was running on this newsgroup a month ago. EXAR XR-2123 is a PSK modulator/demodulator IC which was designed for Bell Standards 201, 212A or CCITT Standard V.22 (1200 Baud), or V.26 (2400 Baud) modems. The information in the EXAR data book about this IC explains in detail how the demodulation is achieved. Both carrier and data recovery are well explained. In addition, a typical modem circuit using the XR-2123 and other ancillary EXAR ICs is given. Anyone wanting to learn how PSK demodulation is carried out would find the EXAR databook of great value. Motorola make a pair of ICs, the MC 6172 and MC 6173 which also modulate and demodulate PSK signals. Application Note AN 870 covers the use of these ICs and presumably describes their operation but as I have not seen a copy of the note, I cannot comment further. These days of course, modem speeds for most purposes are very much higher than 2400 Baud and the signal modulation/demodulation is achieved by digital signal processing. The EXAR and Motorola ICs described above are therefore effectively obsolete. I wish to make a 2400 Baud modem card which will fit inside the my TNC-2 work-alike Packet Controller and connect to its expansion header. This will allow me to use the V.26 protocol port instead of the 1200 Baud FSK port on the local bulletin board. Why is there a V.26 port you ask? Well, a number of commercial modems of this protocol became available, were snapped up by the local hams, adapted for packet radio use and put into service. Question 1: Are the EXAR XR-2123 or Motolola MC 6172 and MC 6173 ICs available now from any source. If so, can someone please advise the source and cost on a one-off basis. They are unobtainable in this part of the world. Question 2: Is there a DSP design (in either kitset or constructional information plus software form) available for me to build. If so, I would like to know the source and cost. ............................................................... ! Jim Parnell ZL2APE ! ! ZL2APE@ZL2WA.#60.WLG.NZL.OC 87 Duncan Tce ! ! Kilbirnie ! ! Wellington ! ! National Organiser for the NEW ZEALAND. ! ! Jamboree on the Air in New Zealand. ! !.............................................................! ------------------------------ Date: Sat, 23 Apr 1994 10:38:39 GMT From: pacbell.com!amdahl!netcomsv!netcom.com!equis@ames.arpa Subject: QRP neswwsgroup To: ham-homebrew@ucsd.edu hi brien: Yeah, I really thought, naively, that "homebrew" corresponded to actual beer. I know I'm just vaguely anonymous but I subscribed to this news group out of an interest in the art of properly fermented yeast. I'm trying to find the connection to amateur radio. Please help. Brien Pepperdine (pepperb@govonca.gov.on.ca) wrote: : Oh please, I think, I suspect, I know for sure (I believe) that there is : QRP usenet/newsgroup for radi amateur qrp interests and building. Could : anyone tell me what the rec. or whatever group is called (i.e. : rec.radio.amateur.low-power ?) I am new, and my key word searches are not : quite so great. : Thanks. Any info as to where to hang out for such things would be : appreciated. I figured the homebrew area would know about such a closely : associated thing as qrp. : 73 de VE3VAW ------------------------------ Date: 24 Apr 1994 14:00:06 -0400 From: ihnp4.ucsd.edu!usc!math.ohio-state.edu!howland.reston.ans.net!europa.eng.gtefsd.com!news.ans.net!hp81.prod.aol.net!search01.news.aol.com!not-for-mail@network.ucsd.edu Subject: QRP neswwsgroup To: ham-homebrew@ucsd.edu Actually, you might combine both: homebrew and hombrew radio! I've tried it and it seems to work well--not at all like those Miller commercials might suggest. 73 de JimN0OCT ENTROPY AINT WHAT IT USED TO BE! ------------------------------ Date: Mon, 25 Apr 1994 05:27:12 GMT From: ihnp4.ucsd.edu!library.ucla.edu!csulb.edu!csus.edu!netcom.com!mont@network.ucsd.edu Subject: R2 T2 pcb source wanted To: ham-homebrew@ucsd.edu In article <2oojok$226@search01.news.aol.com>, JimN0OCT wrote: >In article <1994Apr14.132347.26126@news.mentorg.com>, jbate@rtp-nc.mentorg.com >(John Bate) writes: > >>I'm trying to find a source for the R2 and T2 pcb as > >From reading similar threads and hearing the experience of some local hams, you >might try calling him. I was just about to make out a check for the R2 board >myself (sourced all of the parts already). That is the direction I'm going to >pursue. Well, I ordered some boards from Applied Radio Science in Dec. 1993. I just received the order with $5 refund on shipping. Funny thing is, the return address on the envelope is: Campbell Rt 1 Box 195 Chassell, MI 49916 The boards are very well made and I'm glad to get them. 73, -- Mont Pierce +-------------------------------------------------------------------------+ | Ham Call: KM6WT Internet: mont@netcom.com | | bands: 80/40/20/15/10/2 | | modes: cw,ssb,fm | +-------------------------------------------------------------------------+ ------------------------------ Date: 21 Apr 1994 22:21:08 -0700 From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!math.ohio-state.edu!news.acns.nwu.edu!ftpbox!mothost!lego.wes.mot.com!mdisea!mmddvan!vanbc.wimsey.com!vanbc.wimsey.com!not-for-mail@network.ucsd. Subject: TI 320C26 DSP Eval Kit To: ham-homebrew@ucsd.edu I bought the TI C26 DSK last fall. I suggest you look at ftp orst.edu (don't remember the exact address) or email forrerj@FRL.orst.edu for his (johann Forrer) port of the W9GR DSP noise reducer/notch to this unit. Look also for some other dsp modems; some of them with a [well justified] price attached. Does it meet my expectations? Yah. Comes with RCA phono jacks in and out; 16-bit I think a/d and d/a conv, sample up to 30 or 50 khz; lotsa demo software at ti.com via ftp or a couple of other sites (one in Australia). Bought a book - PC-DSP. Best 30 bucks I've spent in a while - it's been superceded I think, probably even better - disks with programs etc to design FIR, IIR and other goodies. Makes coefficients that can be loaded into the DSK via it's D9 RS232 port. [I forgot to mention that, didn't I...] Then again, I'm just a learner. Check Arrow, other TI distribs. They were short of stock a few months back. Great bargain. There's a rumored C51 versio, but it keeps getting delayed. Cheers / Mark ------------------------------ Date: Sun, 24 Apr 1994 22:57:42 -0800 From: ihnp4.ucsd.edu!usc!howland.reston.ans.net!news.intercon.com!panix!zip.eecs.umich.edu!newsxfer.itd.umich.edu!nntp.cs.ubc.ca!cyber2.cyberstore.ca!nwnexus!bellevue-ip34.halcyon.com!user@@. Subject: TUBE WANTED: CK-1905 To: ham-homebrew@ucsd.edu Does anyone have one or two CK-1905 "nixie" tubes you'd be willing to sell for $10 ea or less? -- James Baker Seattle, WA jbaker@halcyon.com ------------------------------ End of Ham-Homebrew Digest V94 #110 ******************************