Date: Sun, 19 Dec 93 04:30:30 PST 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 V93 #137 To: Ham-Homebrew Ham-Homebrew Digest Sun, 19 Dec 93 Volume 93 : Issue 137 Today's Topics: chirping oscillator (2 msgs) Heathkit DX-60B Mod? (2 msgs) Intercom info available from author Ramsey 6m (2 msgs) 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: 17 Dec 93 16:12:07 EST From: titan.ksc.nasa.gov!k4dii.ksc.nasa.gov!user@ames.arpa Subject: chirping oscillator To: ham-homebrew@ucsd.edu In article <1993Dec16.213126.9152@cactus.org>, majec@cactus.org (Majec Systems) wrote: > The Sad Tale of a Musical Oscillator, Or how I'll spend my Xmas vacation > Well, what that silly first line was meant to allude to was the fact that > I have a chirping, whooping, and generally being anything but, stable > oscillator. Ed- I'm not familiar with the Ten-Tec, but other chirping oscillators have problems with voltage regulation, and unstable loads. Aside from improving the voltage regulation, you might try leaving the oscillator on continuously during transmit, and keying a subsequent stage. In the latter days of vacuum tube transmitters, "grid-block" keying was used to accomplish that. Earlier transmitters put the key in the cathode of one of the later stages. Other QRP transceivers have a circuit to slightly change the frequency of the VFO, to provide approximately 800 Hz offset between transmit and receive frequencies. If yours does this (and it probably does), that offset circuit may be contributing to the chirp. ARRL has published a couple of volumes, containing summaries of QST Hints & Kinks related to problems with QRP rigs. If you have access to a store that carries them, you might take a look for your Ten-Tec. 73, Fred, K4DII ------------------------------ Date: Thu, 16 Dec 1993 21:31:26 GMT From: ucsnews!sol.ctr.columbia.edu!howland.reston.ans.net!gatech!swrinde!cs.utexas.edu!cactus.org!majec@network.ucsd.edu Subject: chirping oscillator To: ham-homebrew@ucsd.edu The Sad Tale of a Musical Oscillator, Or how I'll spend my Xmas vacation Well, what that silly first line was meant to allude to was the fact that I have a chirping, whooping, and generally being anything but, stable oscillator. As CW is my preferred form of rf emission this chirping oscillator just won't cut it. Here are the specifics. The rig is a TEN-TEC pm2 (early 70's qrp rig) It's a direct conversion style transceiver. "The oscillator used for receiving operates directly at the frequency being received. This allows the same oscillator to be used for transmitting. When the XTAL/VFO switch is placed in the VFO position, it connects the receiving oscillator output in place of the crystal." This is a fairly crude design in my opinion.The DPDT switch has single conductor hookup wire going from the switch to the board (six of them) about 2.5 inches long. The switch selects between 80m and 40m lc circuits which feed the base of the bipolar transistor, the oscillator. The oscillator is followed by a buffer and then the XTAL/VFO switch. After the XTAL/VFO switch is the driver stage and the final. That's it on the radio Soooo, what how about suggestions on improving the stability of the oscillator. By the way there is no shielding around the transistor section of the oscillator, the inductor is in a metal can but that's it. Any suggestions would be appreciated. I am going camping down into Mexico and want to use my new (to me) VFO capable radio as opposed to my MXM rock bound QRP rig. Thanks in advance. Ed Guinn kb5ruf majec@cactus.org ------------------------------ Date: 17 Dec 93 20:18:36 GMT From: ogicse!cs.uoregon.edu!sgiblab!sdd.hp.com!col.hp.com!srgenprp!alanb@network.ucsd.edu Subject: Heathkit DX-60B Mod? To: ham-homebrew@ucsd.edu Michael Fortner (ncc2001@cwis.unomaha.edu) wrote: : Hello all! I am wondering if there is anyway I can add SSB to my : Heathkit DX-60B (currently CW/AM) so I can do 10M SSB. I would prefer : a "black box" between the transmitter and the antenna, although a : hardware modification would be considered. There was a box called the Heath SB-10 which converted a DX-100 or Apache transmitter to SSB. With suitable modifications to the DX-60, you could probably get it to work. It would not be a simple mod. AL N1AL ------------------------------ Date: Fri, 17 Dec 1993 20:18:16 GMT From: mvb.saic.com!unogate!news.service.uci.edu!usc!howland.reston.ans.net!sol.ctr.columbia.edu!news.unomaha.edu!cwis.unomaha.edu!ncc2001@network.ucsd.edu Subject: Heathkit DX-60B Mod? To: ham-homebrew@ucsd.edu I do not think it is worthless to try to convert this piece of equipment. Many newer hams (myself included) can not afford the outragous prices of new and "newer" used equipment. However, we can afford and often enjoy modifying what we can afford. It is much better to take a piece of working electronics and keep it useful than have it take up space in a landfill. 73 de N0YBC Michael -- | Michael Fortner N0YBC | DOCTOR! DOCTOR! DOCTOR!... | | Internet: ncc2001@cwis.unomaha.edu | Well, what's your problem? | | Packet: N0YBC@WB0BLR.#SWIA.IA.USA.NA | My brain hurts! | | | It'll have to come out then! | ------------------------------ Date: Sat, 18 Dec 93 00:34:53 GMT From: mnemosyne.cs.du.edu!nyx10!jmaynard@uunet.uu.net Subject: Intercom info available from author To: ham-homebrew@ucsd.edu A couple of months or so ago I mentioned that there were plans running around for a homemade VOX intercom that was designed for aircraft use, but would also be useful for multiop contesting. I've finally found the info again. If you're interested, drop email to Dave Allen, WB0TAQ, at davea@col.hp.com. He'll pass along an ASCII schematic, parts list, and information document. The folks who have built it so far report good success with it, although Dave cautions that some extra bypassing may be necessary in a high-RF environment. I haven't built it yet, though it's on my list of things for the next Field Day... -- Jay Maynard, EMT-P, K5ZC, PP-ASEL | Never ascribe to malice that which can jmaynard@oac.hsc.uth.tmc.edu | adequately be explained by stupidity. "A good flame is fuel to warm the soul." -- Karl Denninger ------------------------------ Date: 17 Dec 93 19:56:13 GMT From: aio!usenet@ames.arpa Subject: Ramsey 6m To: ham-homebrew@ucsd.edu In article v087jsfu@ubvms.cc.buffalo.edu (Danny Anderson) writes: >Did anyone see the Ramsey 6m kit? The ad says a 12 year old did the 2m >kit. It would be real embarrassing if I ordered one and couldn't get it >to work. Does anyone do 6m? In our area there is about 7 repeaters. >Would it be safe to say, that you would not find anyone or hardly anyone >on them? If I got one, how do you check when the radio is good for DX? >If the conditions for DX are good do the repeaters still work? > >N2UPM >Dan > Has anyone built the Ramsey 6m Rig. I have been considering building one and would appreciate any feedback. Thanks, John Maca NASA-Johnson Space Center jmaca%jscdk@jesnic.jsc.nasa.gov ------------------------------ Date: 19 Dec 93 01:21:10 GMT From: mulvey!rich@uunet.uu.net Subject: Ramsey 6m To: ham-homebrew@ucsd.edu Danny Anderson (v087jsfu@ubvms.cc.buffalo.edu) wrote: : Did anyone see the Ramsey 6m kit? The ad says a 12 year old did the 2m : kit. It would be real embarrassing if I ordered one and couldn't get it : to work. Does anyone do 6m? In our area there is about 7 repeaters. : Would it be safe to say, that you would not find anyone or hardly anyone : on them? If I got one, how do you check when the radio is good for DX? : If the conditions for DX are good do the repeaters still work? Dan: Ramsey kits are generally considered to be bottom-of-the-barrel quality, especially when you consider that they tend to have lots and lots of spurious emissions, without ( undocumented ) modifications. They can be useful as a starting point for parts, etc, but don't expect to get a rig that meets FCC standards without some redesigning. - Rich -- Rich Mulvey Amateur Radio: N2VDS Rochester, NY rich@mulvey.com "QRP is not for sissies" ------------------------------ End of Ham-Homebrew Digest V93 #137 ****************************** ******************************