Daily GLOWBUGS

Digest: V1 #63

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Purpose: building and operating vacuum tube-based QRP rigs

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Subject: glowbugs V1 #63
glowbugs            Tuesday, June 24 1997            Volume 01 : Number 063

Date: Sun, 22 Jun 1997 20:15:03 -0500 (CDT) From: Kevin Pease <hamradio@mm1001.theporch.com> Subject: Globug Rig I just got my new glowbug rig working. I still have some mechanical things to do but it is now putting out a pretty good CW signal. I call the rig the 80/40 Meter Peble Pulveriser Deluxe. It is a full dual conversion band image super het for 80 and 40 meters with an old DRAKE RV3 dial drive and PTO for the main tuneing. It uses a 1700 KHZ first IF followed by a collins 800 HZ CW mechanical filter and single IF stage feeding a 12AU7 product detector. It has two stages of audio useing 1/2 of a 12AX7 and a 6AQ5 for output. The audio power is not as good as I am used to with 5 watt IC's but it sounds good on CW so I am happy. It also has audio derived AGC for my tired old ears. Ithe first mixer is a 6EA8 or 6U8 with a 6AU6 for VFO and half of the 6U8 as the VFO buffer. There is no VFO pulling and the rig is pretty stable. I also have a 6BA6 RF amplifier for the selectivety and gain. This rig is pretty HOT. I can hear good signals on just a wire across the floor. It hears real good on the Inverted VEE. The Transmitter is a 6BM8/ECL-82 triode pentode. It is crystal controlled. I would like to build a VFO for it. Maybee that can bee my next project. an 80/40 meter VFO would be pretty easy to build. The 6BM8 is pretty amazing. it is about the size of the 5763 pentode and puts out 7 watts on 40 meters. It puts out about the same on 80 Meters. The plates on this tube don't even glow. I am useing the receiver to monitor the transmitted signal for a cw sidetone so I cant operate too large a split or I will have no sidetown for my key pounding. I would like to know where the circuit is for the neon oscilator sidetone that has been published. That would allow me to mute the RX and also operate a wide split for those rockbound people who call me off frequency. I only have three crystals at this time and only one is usefull I have a 7150 which is good for band calibration I also have a 3990 which is useless but I am useing it to test the transmitter on 75 meters. The only usefull crystal is on 7045 khz. it is not on the 7050 qrp frequency and not on the new 7060 frequency but it is noot in too bad a spot. If anyone can work 7045 then maybee I can work someone from this list. This whole rig is in a box 6.5 inches tall 9 inches wide and 8.5 inches deep. It is pretty small. It was a chalenge getting everything into the small box but I started out real simple building a regenerator and tx in one box and ended up building a cadalac. I was going to try transceive but the second and fourth harmonic of 1700 khz are too close the the ham bands whisc would make it hard to get rid of the spurious signal so it is split only. It has been great fun getting this little rig running. It brings back fond memorys from my youth of sitting out at the picknic table in the back yard under the birch tree building tube receivers. It has been a fun trip down memory lane. This project is not complete. I have an Smeter and Relout-put meter to connect and as mentioned above I would like to build a temp compensated external VFO for the transmitter in a small box as a companion to this rig so that I don't have to bee rock bound. Does anyone know who was offering the deal on a bunch of XTALS for 80 and 40 meters in ft-245 cases for us globugites ? I definately need to buy more xtals untill I can get the VFO running. I need the xtals anyway for the simplicity and maybee portable use at field day or something. I can see that this rig will get used alot. I am going to put it in my bedroom for late night use into a small dipole on 40 meters. As a side thought I know htat this is glowbug herisy but I am thinking about building a DDS synthysizer into a real small box that will plug into the xtal socket and be a digital xtal replacement. I may even use thumbwheel switches for frequency input. It would be real stable and small and a neat digital xtal thingee. Kevin Pease WB0JZG Mount Juliet, TN.
Date: Sun, 22 Jun 1997 20:21:47 -0500 (CDT) From: Kevin Pease <hamradio@mm1001.theporch.com> Subject: PI-Networks On the subject of PI-Net outut networks. I use the formula in my 1991 handbook to calculate the impdance for my glowbug rig useing class C and used some miniductor cut per the tables in the same handbook and the rig loads up just fine on 80 and on 40 meters by shorting out about half of the coil. I have heard the previous discussion about PI-NET discrepancies and I can verify that what is in the handbook works just dandy. By the way my little 6BM8 puts out 7-8 watts on just 10 to 11 watts input. Pretty good eficency from an old tube. If I include the filament power the eficency isn't quite as good. since the filament consumes 1.89 watts uping the input power to abiut 13 watts. Kevin Pease WB0JZG Mount Juliet, TN.
Date: Sun, 22 Jun 1997 20:06:13 -0700 (PDT) From: techni@netcom.com (harold meltzer) Subject: R-1004 Still searching for an R-1004 receiver,p/o AN/GRC-109. Harold Meltzer
Date: Sun, 22 Jun 1997 21:11:26 -0600 (MDT) From: James P Rybak <jrybak@mesa7.mesa.colorado.edu> Subject: Old QSTs For Sale I have the following issues of QST for sale as a lot. All have attached covers and some are almost like new. 1933 Nov. 1934 April 1935 July, Sept. 1936 April, Dec. 1937 Feb., June, Aug. 1939 July, Oct., Nov., Dec. 1940 Jan., April, Aug., Sept 1941 June, July, Sept. These old QSTs are a lot of fun to read. These magazines were published before most of us were born. The cover photos and ads alone make the magazines worth getting. There also are a lot of interesting glowbug construction articles. I will sell the entire lot of 20 for $35 plus $8 for shipping. The price is fixed and I will not break up the lot unless the entire lot does not sell. Then the cost will be $2.50 plus shipping per issue. Thanks. Jim W0KSD
Date: Sun, 22 Jun 1997 20:30:38 -0700 (PDT) From: Ken Gordon <keng@uidaho.edu> Subject: Re: Globug Rig > usefull crystal is on 7045 khz. I can listen for you on 7045 and I have both a 7048 and a 7050 rock for my AN/GRC-109. I generally get on about 0230 and again at about 0430 or so. Sounds like you did a really neat job on it. 73, Ken W7EKB
Date: Mon, 23 Jun 1997 04:08:22 -0700 (PDT) From: Ken Gordon <keng@uidaho.edu> Subject: 7050/7060 last night... called on 7050 at 0230 and again 0430. Nothing heard. Called CQ on 7015 immediately answered by K7EW, Steve in Portland, Oregon. He was running 1 watt to a dipole. 569/579. Nice chat. He was quite familiar with the GRC-109. Couldn't even hear him on the SB-301 (gonna have to check that thing out). Q-5 copy on the R-1004 since 1L6 replaced with better tube. Details at 11:00. Ken W7EKB
Date: Mon, 23 Jun 1997 10:24:34 -0400 (EDT) From: "Walter L. Marshall" <wmarshal@CapAccess.org> Subject: xformers needed I need these so I can fire up some of the radios I have without power supplies. The idea is to put them all in one box, and have a universal power supply. 22, 45, 67, 90, 135, 180 volts. Any, or all of these desired. No pole pigs, please. Lon
Date: 23 Jun 1997 10:40 EDT From: "Richard Crapse" <rwcrapse@nortel.ca> Subject: anybody know the current prices? a Friend of mine has the following going on the market: A Drake SSR-1 and Heathkit TR-108 Any clues as to their abilities and average market prices would be appreciated. Thanks, Rick KB4TKQ
Date: Mon, 23 Jun 1997 18:29:08 +0000 From: Sandy W5TVW <ebjr@worldnet.att.net> Subject: Re: xformers needed At 02:24 PM 6/23/97 +0000, you wrote: > I need these so I can fire up some of the radios I have >without power supplies. The idea is to put them all in one >box, and have a universal power supply. > 22, 45, 67, 90, 135, 180 volts. > Any, or all of these desired. No pole pigs, please. > Lon > Lon, Sounds like some "battery" gear! Your best best would be to Use a 250-0-250 or so volt power transformer @ 70-90 ma. Use voltage dividers and zener diodes to get your various voltages. I've used that scheme and it works really well. Also consider using the 5 volt filament winding to supply a diode bridge and a single TO-220 chip adjustable regulator to obtain either 1.5 or 2.0 volts for a DC filament supply. You can use the same winding and another bridge rectifier to get a -3 or -4.5 volt "C" supply as well. I opted to use "AA" pencells as there is NO drain on the "C" supply usually. That way you can build a supply that will furnish 6.3 VAC and a 180-250 volts plate supply or the common battery voltages you encounter commonly: 22.5, 45, 67.5, 90, 135 volts. (I use 24, 48, 68 volt zener diodes at 5 watts on my unit) 73 E. V. Sandy Blaize, W5TVW "Boat Anchors collected, restored, repaired, traded and used!" 417 Ridgewood Drive, Metairie, LA., 70001 ebjr@worldnet.att.net **Looking for: 860 tubes, WL-460 tubes** **Butternut HF2V antenna, G-R test gear.....................***
Date: Mon, 23 Jun 97 13:37:53 PDT From: "Adam McLaughlin KD6POC" <kd6poc@jps.net> Subject: Link Coupled Matchging Networks Hello There, fellow Glowbuggers! Today I finished assembling my link coupled antenna tuner for my antenna.= It works great! I can get the SWR down flat on this jig, and this makes = the transmitter happy. Now, the questions. Has anybody else out there used one of these before well enough to guide = me through the troubleshooting process? And, how well can you receive signals through them? Do they do a good job= of transfering the RF on receive? Do these tuners increase feed line radiation in any way? How do they affe= ct any harmonics or RFI/TVI situations? Thanks, Adam McLaughlin KD6POC QRG: 7037 KHz kd6poc@jps.net http://www.jps.net/jmclaugh MTC-ARRL-FISTS #3366
Date: Mon, 23 Jun 1997 16:23:19 -0500 (CDT) From: Bob Roehrig <broehrig@admin.aurora.edu> Subject: Re: Link Coupled Matchging Networks Hi Adam. One thing you didn't say - are you feeding open wire line with it or what? Efficiency is the same on transmit or receive. If it talks well, it should listen well too. If you are feeding balanced line and the whole antenna system is balanced, the feedline should not radiate noticeably. The only time I have had problems with such an arrangement is when the impedance on the feedline side is very high - RF all over the shack. I don't like voltage fed antennas! How did you build the link? A good thing to do is to have the link electrostatically shielded from the tuned coil. Look in the Antenna handbooks on link coupling circuits. Even in plate tanks that are link coupled, they describe how to shield the link. That helps reduce TVI. I usually do it by making the link out of coax cable. Strip the end of the coax and tape the end of the shield. Then connect the center conductor back to the shield at the start of the link winding. E-mail broehrig@admin.aurora.edu 73 de Bob, K9EUI CIS: Data / Telecom Aurora University, Aurora, IL 630-844-4898 Fax 630-844-5530
Date: Mon, 23 Jun 1997 16:54:13 -0500 From: Bob Liesenfeld <wb0poq@visi.com> Subject: Tuner Now, the questions. > Has anybody else out there used one of these before well enough to guide me >through the troubleshooting process? > And, how well can you receive signals through them? Do they do a good job of >transfering the RF on receive? >Do these tuners increase feed line radiation in any way? How do they affect any harmonics or RFI/TVI situations? Hmmmm.... Well I could use a bit more info on the particulars of this tuner, but I belive that an inductively coupled tuner should pass less harmonic energy to the load that the more familiar "T" config, all else being equal. I know that inductively coupled tanks with variable coupling along with a Faraday shield were popular years ago, especially with balanced high Z feedlines. An older copy of the ARRL Handbook should offer much on the subject. 72 - -- Genuine E-mail From the Land of the Everlasting Icicle... Bob Liesenfeld wb0poq@visi.com
Date: Tue, 24 Jun 1997 00:23:14 -0700 From: Gerald Caouette <ve6nap@oanet.com> Subject: Tubes 4 sale I have the following tubes As I only want a few of these for my own use I am offering the rest for sale I have 450 NIB/NOS JAN 5933 valves These are a military equivelent to the 807 Same base, pin out and electrical specifications But Mil spec. for long life and relaibility looking for $6.00 U$ each or 4 for 20.00 U$ 10 for 45.00 U$ 50 for 200.00 U$ ( 1 case ) 100 for 375.00 U$ ( 2 cases ) I have military reaining clamps for the 807/5933 and other tube with the same base . Single screw mount toggle type clamp looking for $2.00 U$ each I have 60 Jan 7645 Twin tetrodes for sale NIB/NOS in original Westinghouse Boxes and would like $ 3.00 U$ each or 5 for 12.00 10 for 20.00 I have 10 NIB/NOS Eimac/ Varian JAN 8167 / 4CX300A Metal Ceramic tubes These list for over $200.00 each I would like $ 55 U$ each or 2 for $100.00 U$ 3 for $145.00 U$ 4 for $180.00 U$ I have 50 NIB/NOS JAN 5719 miniature triodes and would like $ 2.50 U$ each or 5 for $10.00 U$ 25 for 48.00 U$ 50 for $90.00 U$ Metal Enclosed Relays - - New time delay relays Flange mount Solder terminals 6.3 Volt heater SPST N.O. 3A @ 250 VAC your choice 60 Second or 85 Second version Great for soft starting that Amp and reducing the thump when you turn on your amp. $ 5.00 each - - NEW sealed metal case relay Mil Spec 25267-A1 Class B8 4 point stud mount Solder terminals 115VAC coil with internal 1/2 wave rectifier Works ok at 48 VDC 4PDT 5 Amp @ 28 VDC or 115VAC up to 400 HZ leach corp / Part # 9220 - 4186 $ 20.00 each $ 30.00 for 2 TRW Cinch terminal strips NEW - Part # 10-172-Y $10.00 for a box of 10 terminal strips All prices are in US funds Shippng costs are extra email if intrested to ve6anp@oanet.com Edmonton, Alberta, Canada
End of glowbugs V1 #63 **********************
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