Date: Fri, 26 Aug 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 #253 To: Ham-Homebrew Ham-Homebrew Digest Fri, 26 Aug 94 Volume 94 : Issue 253 Today's Topics: 2M to FM bcast band converter 2 M to FM Broadcast Reply 4-1000 Homebrew Amp 40m ANT Flavor radio SW? FM transmitter Ham-Homebrew Digest V94 #252 handicnt.zip - Optoelectronic 3000A & M1 handicounter reviews Help designing Capacitor Impedance Match Network mlhacker.zip - Zenith Minisport docs, hints, hacks & goodies Question from a newbie regenerative sets and selectivity Where to buy kits? 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: Wed, 24 Aug 1994 20:55:34 GMT From: news.Hawaii.Edu!kahuna!jeffrey@ames.arpa Subject: 2M to FM bcast band converter To: ham-homebrew@ucsd.edu In his excellent reply to my idea ka7oei@uugate.wa7slg.ampr.ORG writes: > > If you look in a recent ARRL Radio Amateur's Handbook >(you *do* have one of those, don't you, and why not??? I get a new >one about once every 5-6 years... Enough has changed by then:-) Ummm, I like to let a little more time go by than 5-6 years; I have the 1950, 1972 and 1991 editions. I'll wait until about 2010 to get another. 73 and thanks for your valuable ideas. Jeff NH6IL ------------------------------ Date: Wed, 24 Aug 1994 20:46:28 GMT From: news.Hawaii.Edu!kahuna!jeffrey@ames.arpa Subject: 2 M to FM Broadcast Reply To: ham-homebrew@ucsd.edu In article <9407247777.AA777747053@mails.imed.com> mack@mails.imed.COM (Mack Ray) writes: > Jeff: > > This sounds like a good idea on the surface, but it has some very > serious technical problems. FM broadcast is wideband FM (VERY > wideband) whereas amateur is narrow band. The bandwidth of an amateur > signal is about 15KHz (give or take a little) with channels either > every 15KHz or 20KHz depending on where in the US you are. If things > have changed in the last 5 years they may all be 20KHz now. Broadcast > bandwidth is 200KHz. So you see if you use the broadcast radio you > will actually be listening to 10 amateur frequencies at once. Hi Ray: I did mention this in my article when I said: ``...the selectivity will be awful (what's the bandwidth of an FM station?)....'' but in an area with few active repeaters (such as here in Hawaii) it might not be too bad. Hadn't thought about the low audio, though; I'll just turn the volume up ;) Remember, this project is just for fun - don't take it or me too seriously. Jeff NH6IL ------------------------------ Date: 24 Aug 1994 20:21:12 -0400 From: newstf01.cr1.aol.com!search01.news.aol.com!not-for-mail@uunet.uu.net Subject: 4-1000 Homebrew Amp To: ham-homebrew@ucsd.edu In article , Tom Skelton writes: TOM, I AM PLANNING A PASSIVE GRID CIRCUIT with screen voltage. Are you aware of this technique? I have had one reply by someone aware of this and it sounds ok . The idea is a universal Amp for all HF as needed. I'm also using a Powerstat on the Plate, screen and filament so I should be ready for any eventuality. I already had most of the parts. How big a plate capacitor do you want? I do run into them from time to time. I managed to acquire vacuum caps for this one. Thanks for the comments. Any info is most welcome. Gud Luk with your "Ne plus ultra" 73 & gud DX Russ Ellsworth WA6CWV..Boise, Idaho ------------------------------ Date: 25 Aug 1994 15:33:14 GMT From: zib-berlin.de!news.belwue.de!news.uni-stuttgart.de!deap1032@uunet.uu.net Subject: 40m ANT To: ham-homebrew@ucsd.edu Hi Rob, Two friends of mine (DL3SDN, DL6SDW) solved the very same problem with a long wire hung out of the window and along the lamp posts in the street. 80 or so meters long. It works fine for DX. I once used a quarterwave out of the window, but thats to short. 73, Moritz DL5UH ------------------------------ Date: 24 Aug 1994 20:42:07 GMT From: hplextra!news.dtc.hp.com!col.hp.com!fc.hp.com!amw@hplabs.hpl.hp.com Subject: Flavor radio SW? To: ham-homebrew@ucsd.edu I'm looking for information on taking a cheap Radio Shack AM radio (The colored ones they sell as "Flavoradio's") and adding a selector switch and a set of coils to change the frequency range to allow SW reception. There was an article on doing this in one of the electronics mags (Radio Electronics, Popular Electronics, ... ) two or three years ago but I just saw it in passing and can't remember which magazine or when it was printed (My best recollection is that it was Nov-Dec-Jan of '91). If anyone remembers this or has some general comments on this type of conversion, let me know. Andy Weilert amw@fc.hp.com ------------------------------ Date: 25 Aug 1994 00:12:16 GMT From: solaris.cc.vt.edu!usenet@uunet.uu.net Subject: FM transmitter To: ham-homebrew@ucsd.edu I was looking for the schematics on how to build a FM transmitter, maybe even a transceiver later on down the road. I have the schematics for one that was e-mailed to be, but it never worked. I would like it to be simple if possible. Any help would be appreciated. * * Art ------------------------------ Date: 25 Aug 94 16:01:22 GMT From: news-mail-gateway@ucsd.edu Subject: Ham-Homebrew Digest V94 #252 To: ham-homebrew@ucsd.edu ref Ham-Homebrew Digest V94 #252 article: 24 Aug 94 19:46:52 GMT From: ihnp4.ucsd.edu!sdcc12!jeeves!daniels@network.ucsd.edu Subject: ss delay relay ? > I've got an Omnetics Inc. solid-state delay relay that I need >the pin-out for. Part # MMS115A5Y60A, with four spade lugs numbered > 1 - 4. The surplus shop I got it from says it's an adjustable > delay, but I'm pretty sure it's a fixed 60-sec delay. Does > anyone have any information on this part or know the > address/phone # of Omnetics? Many thanks for any help mark > daniels daniels@jeeves.ucsd.edu a quick look on a CD ROM data base yields Omnetics ph # 315-699-5262 PO box 2577 Syracuse, NY, 13220-2577 Tech data is terse and does not include pin out: 115 vac spst 1 amp rms steady 20 ma min The NSN data indicates the company was in process of being sold at time the data was entered. CD-ROM data base is copy of Defense Logistic Supply Center Data, No spares procurment history. No other PN assigned to same NSN. GOOD LUCK in applying it. 73, K5VMU Dale_Croft@comsys.rockwell.com Integrated Logistic Support Mgr My opionions may not be shared or endorsed by Rockwell, YMMV ------------------------------ Date: Thu, 25 Aug 1994 02:41:56 GMT From: ihnp4.ucsd.edu!dog.ee.lbl.gov!agate!howland.reston.ans.net!europa.eng.gtefsd.com!ulowell!simtel.coast.net!msdos-ann-request@network.ucsd.edu Subject: handicnt.zip - Optoelectronic 3000A & M1 handicounter reviews To: ham-homebrew@ucsd.edu I have uploaded to the SimTel Software Repository (available by anonymous ftp from the primary mirror site OAK.Oakland.Edu and its mirrors): SimTel/misc/hamradio/ handicnt.zip Optoelectronic 3000A & M1 handicounter reviews handicnt.zip contains two text documents, reviewing Optoelectronic's 3000A and M1 handicounters, capable of time domain measurements on directly coupled and RF signals up to the gigahertz range. These have attained leading market position and are advertised in most Amateur Radio/electronic magazines. I have owned both of these meters and after running them them through the ringer, summarized my findings in these technically accurate reports, unbiased by advertisement dollars. Other users and possible owners will be interested in what they can - and can't - do. FreeText. Uploaded by the author. Brian Mork bmork@opus-ovh.spk.wa.us ka9snf@ka7fvv.#ewa.wa.usa 6006-B Eaker, Fairchild, WA 99O11 V:509-244-3764 D:509-244-9260 ------------------------------ Date: 25 Aug 1994 07:30:59 -0700 From: nntp.crl.com!crl2.crl.com!not-for-mail@decwrl.dec.com Subject: Help designing Capacitor Impedance Match Network To: ham-homebrew@ucsd.edu David_Shalita.ES_AE@xerox.COM wrote: : : To: qrp-digest@think:com Ham-Homebrew@UCSD.Edu : 8-24-1994 : : I need help calulating the capacitor values in this capacitor impedance : matching network. See enclosed figure. : : 1. Given: : LC tank, L = 4.7 uh, Q =40, F operating = 10.7mhz, TOKO PN TK3149 : Tank fed from NE-602 Mixer output pin 4, source Z = 1.5 K. : FL1 10.7 mhz Ceramic Filter, TOKO type CFSK TK2306 Since you are using a relatively low Q inductor, it will be advisable to lump the equivilent parralel resistance of the coil with the source resistance ov the NE602. The Rp of the inductor is approximately 12.6K. The 12.6K should be added in parrallel with the 1.5K for a virtual source impedance of 1340 ohms. You really want to match 1320 ohms to 330. : : 2. I calculated Ctotal to resonate tank at 10.7 mhz, = 47 pf's Correct. : : 3. The capacitive divider tank must match 1.5K mixer output to the : Ceramic filter FL1 which requires 330 ohm input termination. ...or 1340 to 330 as per the adjustment I mentioned earlier :) : : 4. I need help with design info method for converting 47pf : into 2 or 3 capacitors for the capacitive divider. There are two simultaneous equations that you need to solve: (C2*C3)/(C2+C3) = 47*10^-12 so that you get 47 pF (C2/(C2+C3))^2 = Rout/Rin = 330/1340 In this case, the caps are almost equal since the impedance ratio is very close to 4:1. Use C2=C3=100pF : : 5. Need a general solution to handle any practical impedance match. : For circuit Q's greater than 10, the procedure I outlined is general. : 6. Could use a reference. I have looked unsuccessfully. Solid State Radio Engineering, Herbert L. Krauss, John Wiley & Sons, 1980, ISBN 0-471-03018-X, pp 48-53 -- ------------------------------------------------- Don Miller My opinions are my own! dmiller@crl.com ------------------------------------------------- ------------------------------ Date: Thu, 25 Aug 1994 02:42:38 GMT From: ihnp4.ucsd.edu!dog.ee.lbl.gov!agate!howland.reston.ans.net!europa.eng.gtefsd.com!ulowell!simtel.coast.net!msdos-ann-request@network.ucsd.edu Subject: mlhacker.zip - Zenith Minisport docs, hints, hacks & goodies To: ham-homebrew@ucsd.edu I have uploaded to the SimTel Software Repository (available by anonymous ftp from the primary mirror site OAK.Oakland.Edu and its mirrors): SimTel/msdos/packet/ mlhacker.zip Zenith Minisport docs, hints, hacks & goodies mlhacker.zip is a compendium of newsletters about the Zenith Minisport laptop computer and its use as a packet radio host computer. Zenith offers only minimal and expensive support for this popular but discontinued 8086 compatible notebook computer. Newsletters contain technical notes, construction projects, operating hints, resources, architecture details and other related goodies. The Minisport Laptop Hacker series is the result of owning and repairing Minisports and donations from others on Internet and the Amateur Radio packet networks. Special requirements: None Changes: Compendium includes Minisport Laptop Hacker #1 - #22. FreeText. Uploaded by the author. Brian Mork bmork@opus-ovh.spk.wa.us ka9snf@ka7fvv.#ewa.wa.usa 6006-B Eaker, Fairchild, WA 99O11 V:509-244-3764 D:509-244-9260 ------------------------------ Date: 25 Aug 1994 06:12:40 GMT From: ihnp4.ucsd.edu!agate!howland.reston.ans.net!usc!nic-nac.CSU.net!news.Cerritos.edu!news.Arizona.EDU!seds!enigma@network.ucsd.edu Subject: Question from a newbie To: ham-homebrew@ucsd.edu Hi there: Does anybody know where I can get the source code for Baycom or anything like it? Thanks in advance! Andrew Tubbiolo Enigma@SEDS.lpl.arizona.edu KC7BHW Phys 415a ------------------------------ Date: Wed, 24 Aug 94 13:57:00 PDT From: ihnp4.ucsd.edu!news.cerf.net!mvb.saic.com!news.alpha.net!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!swrinde!sdd.hp.com!svc.portal.com!portal!cup.portal.com!dbell@network Subject: regenerative sets and selectivity To: ham-homebrew@ucsd.edu >>The "super-regenerative" receiver (detector) should also be considered in >>the discussion. I never understood how they worked,... >These things have always puzzled me too. >As my current understanding goes, an oscillator tuned to the >approximate frequency of reception is periodically stopped and then >allowed to restart at a rate of, say, 40KHz. If some received >energy at the right frequency is coupled into the resonant >circuit, the restart tends to be quicker, with a noticable effect >on the current drawn by the oscillator. >The current drawn by the oscillator contains the output signal. >Is this how it works? >Best regards, >Jeroen Belleman Not to my recollection... I missed earlier portions of this thread, but as I understood it, the regenerative circuit was an attempt to boost gain of a receiver stage by adding positive feedback, up to *almost* the point of oscillation. If this point was exceeded, the receiver would become a transmitter, and all received signal would be swamped by the oscillator's current. The super-regen was a design that eliminated the critical hand-tuning of the regen (which had been by tuning the feedback control for each received signal) by allowing the stage to go into oscillation, which (mumble, mumble) increased grid current, which built up a DC voltage by charging a cap across a multi-meg grid-leak resistor, which reduced the gain, driving it out of oscillation... The effect was similar to a sawtooth relaxation oscillator controlling the gain (via grid bias) of the amplifier stage. The operating points were chosen so that the stage 'hovered' about the critical gain level, getting a voltage gain of thousands(?) from a single amplifier stage. Or, something to that effect... :{) Dave dbell@cup.portal.com ------------------------------ Date: 24 Aug 94 14:51:54 EDT From: psinntp!main03!drager.com!landisj@uunet.uu.net Subject: Where to buy kits? To: ham-homebrew@ucsd.edu In article <337t36$7t7@usenet.INS.CWRU.Edu>, sct@po.cwru.edu (Stephen C. Trier) writes: > In article , > Dennis Rice wrote: >> What are the best sources for kits for amplifiers, receivers, >> transmitters, antennas, etc. [lots of good info from Stephen trimmed to save b/w] For antennas, I must also recommend Bill Orr's books: The Beam Antenna Handbook, which has a lot of good design and construction information on Yagis, LPDA's and quads. I also believe that he has published a more generic Antenna Handbook, which is probably worth checking out too. Joe - AA3GN -- Joe Landis - System & Network Mgr. - North American Drager Co. Telford, PA landisj@drager.com | uupsi5!main03!landisj | AA3GN@WA3TSW.#EPA.PA.USA Opinions are mine only, and do not reflect those of my employer. ...Munging Until No Good... ------------------------------ Date: 24 Aug 1994 22:37:17 GMT From: hookup!yeshua.marcam.com!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!math.ohio-state.edu!magnus.acs.ohio-state.edu!csn!col.hp.com!fc.hp.com!wayne@ames.arpa To: ham-homebrew@ucsd.edu References <776791198snz@arkas.demon.co.uk>, , <1994Aug22.134836.8674@dxcern.cern.ch>.co Subject : Re: regenerative sets and selectivity > As my current understanding goes, an oscillator tuned to the > approximate frequency of reception is periodically stopped and then > allowed to restart at a rate of, say, 40KHz. If some received > energy at the right frequency is coupled into the resonant > circuit, the restart tends to be quicker, with a noticable effect > on the current drawn by the oscillator. > The current drawn by the oscillator contains the output signal. > Is this how it works? This is what I remember. These were used mostly on VHF? Maybe ancient versions of the ARRL Handbook have good explanations of what is going on. Wayne ------------------------------ Date: Thu, 25 Aug 1994 16:01:07 GMT From: ihnp4.ucsd.edu!dog.ee.lbl.gov!agate!howland.reston.ans.net!sol.ctr.columbia.edu!news.ess.harris.com!adm01%rfc.comm.harris.com!gdian22@network.ucsd.edu To: ham-homebrew@ucsd.edu References <777331508snz@lfheller.demon.co.uk>, <33a7c1$ndn@meaddata.meaddata.com>, om Subject : Re: WANTED: Source for Signetics NE604 or SA604 IF/FM detector chip : : |> > I am trying to find a source for the Signetics NE604 or the equivalent : Try 624 Kits, the last price list I had from them had it listed as : $1.65 each, or 10 for $14.50. phone 803-573-6677. : Another source is Dan's Small Parts and Kits. : I've ordered parts from both and they are reliable. : I don't have their addresses handy, check the back of QST or 73 magazines. : - Gary N2JGU MY MISTAKE... I was reading ne604 and thinking ne602. Sorry about any inconvenience... again, my error. - Gary N2JGU ------------------------------ End of Ham-Homebrew Digest V94 #253 ******************************