Re: [AMRadio] k1man fined
- Original Message - Hey Phil, Why do you want to continue this part of the discussion after I politely made a retraction earlier this week to the statement above that you quoted me on? Mainly because I was going through some e-mails that had piled up over several days and I did not yet see the retraction when I sent my reply. Don't be so thin-skinned. Not all of us have the time to go through our e-mail every day, especially in this case, where I often have to delete 200 or more spam messages before getting to the ones that I want to read. Phil K2PG
Re: [AMRadio] Triode connecting 803's for a Modulator
From: Mike Dorworth, K4XM [EMAIL PROTECTED] I assume all three grids simply strapped together. Is that correct? In some circuits with triode-connected tetrodes, particularly the 807, the screen grids are driven directly with the audio, and a resistor is placed between the screen and control grids. No, he had the screen and control grid strapped and fed. The supressor was biased in the center tap of the driver transformer with the voltage indicated. I overlooked the suppressor voltage you had listed. With the relatively high positive voltage on the suppressor grid, and audio on the cotrol/screen grid, it looks to me like this would better be called a pentode connected as a tetrode, not as a triode. The suppressor grid, with the steady +DC acts more like a screen grid, and the control/screen grid act like a control grid. Don k4kyv ___ This message was typed using the DVORAK keyboard layout. Try it - you'll like it. http://www.mwbrooks.com/dvorak/ http://gigliwood.com/abcd/
[AMRadio] More CB to 10
Two questions about the conversion of old CB rigs to 10 meters: 1. Has anyone ever tried to add FM to one of those old rigs? Some years ago, an IC was available, the ECG708, that was a complete FM detector. I used one to add FM receiving capability to a Heathkit HW-17A 2 meter AM rig. Many of those CB rigs had excellent receiver sensitivity and they would be great for hitting the local 10 meter FM repeaters. 2. Do any of you remember the boards that Poly-Paks and other surplus outlets sold back when Hy-Gain filed for bankruptcy in the late 70s? These boards were used in several makes and models of AM CB rigs and Poly-Paks also sold the switch used for selecting the 23 channels. Changing a crystal and retuning would move those boards to the AM portion of 10 meters. When the FCC expanded CB to 40 channels, it would not allow the manufacturers to retrofit 23 channel radios that were already in the pipeline, nor would the Commission allow those boards to be expanded to 40 channels (easily doable). Thousands of those boards were dumped and the hit to the bottom line drove Hy-Gain into bankruptcy and helped drive Lafayette out of business. The TRS-80 computer saved Radio Shack at the time. Have any of you converted these boards to 10 meters and used them on the air? I still have a couple of them in storage somewhere and I'm toying with the idea of converting them once 10 meters shows some signs of life...if I can find my schematics. Ten meters is a bit anemic nowadays, but it should be roaring in a few more years. Five watts or less will work the world! Phil K2PG
[AMRadio] FS: Callbooks, Military Manuals, AWA OTB ARC
For Sale: Callbooks, Military Manuals, Antique Radio Classified AWA OTB. All prices plus actual media mailing cost. CALLBOOKS 1937 September, Vol 18 #3, no covers. $5 1953 Summer, some cover wear but pretty nice. $20 1957-58 Winter, cover really beat up, spine taped. $8 1959 Fall, cover loose. $9 1966 Spring, USA, no cover, otherwise good. $5 1966 Summer, USA some page edges bad. $8 1966-67 Winter, Foreign Radio Amateur, cover dirty. $10 1969 Fall, USA, good. $12 1969 Fall, Foreign Radio Amateur, good. $10 1972-73 Winter, Foreign Radio Amateur, good. $10 1987 North American, nice. $12 1989 North American, nice. $12 1993 International, Cover taped on. $5 1993 North American, covers a bi artty. $5 MILITARY MANUALS AF Manual 52-8, RADAR Circuit Analysis, Dept of the Air Force, 1951, reprinted 1961, probably 400 pages, hole-punched with heavy covers. $5 2 copies available AF Manual 52-8 Volume I Electronic Circuit Analysis, Dept of the Air Force, 962, about 400 pages. Superceded the RADAR Circuit Analysis book above. Paperback. $5 DC-1 Principles Of Electricity Laboratory Notes, Signal Corps, Ft. Monmouth, 1950. $3 EM-469 Electricity and Magnetism by Norman E Gilbert, War Dept., 1941. This is a gov't reprint of a commercial text. 545 pages. $5 EM-962 Principles and Practice of Radio Servicing, by H.J. Hicks, 1943. This is a gov't reprint of a McGraw-Hill commercial text. Back cover missing. 390 pages. $5 FM 24-18 Field Radio Techniques, US Army, 1949. Pocket-size. Cover loose. $3 NAVPERS 10622 Electricity, Basic Navy Training Courses, 1945. $5 NAVPERS 10087-A Basic Electronics, Navy Training Course, 1955, 469 pages. Tubes and transistors, receivers and transmitters. Good text. $10 2 copies available. NAVPERS 10189 Electronics Technician 2, Navy Training Course, 451 pages. $9 NAVPERS 93400A -1 through -8, missing -7, Fundamentals of Electronics, Volumes 1 through 8, missing number 7, 1965. Each volume is 125 pages with stiff covers, comb-bound. The volumes are 1A) Basic Electricity-Direct Current, 1B) Basic Electricity-Altrnating Current, 2) Power Supplies and Amplifiers, 3) Transmitter Circuit Applications, 4) Receiver Circuit Applications, 5) Oscilloscope Circuit Applications, 6) Microwave Circuit Applications, Volume 7 is missing, 8) Tables and Master Index. Some volumes run as much as 170 pages. So there's about 1,000 pages here. It's all tube, no solid state. $12 NAVPERS 93400A-4 same as above, volume 4 only $1 NAVTRA-10195-A Electronics Technician 3 and 2, Volume 1, 1972, Naval Training Command, 260 pages with huge fold-outs. Covers sets like WRR-2, WRT-1, URC-9, R-1051, much Teletype, SRR-19 and FRT-39-plus test sets, antennas and wiring. Quite a reference. $12 ORDP 20-139 Servomechanisms Section 4 Power Elements and System Design, Ordnance Corps, 1959, about 200 pages, with covers. $3 ST 24-2-1 Radio Frequency Management, US Army, May 1, 1965. $5 TM 11-499 Radio Propagation Handbook-Preliminary, War Dept., 1943. 200+ pages. No cover-might not have had one. $5 TM 5-5166 Engine Gasoline Continental Model M330, Army, 1952, 228 pages. $5 TM 11-662 Basic Theory and Application of Electron Tubes, Airmy and Air Force, 1952. 212 pages, a good basic text. $9 2 copies available. TM 11-666 Antennas and Radio Propagation, February, 1953. $5 3 copies available. TM 11-669 F-M Transmitters and Receivers, US Army, 1952, 194 pages. $5 TM 11-671 Cathode Ray Tubes and Their Asociated Circuits, Army, 1951, 200 pages. $5 TM 11-678 Fundamentals of Telephony, US Army, 1953, 260 pages. Telephones, switchboards, handsets and wiring used by the army in the '50s. $5 TM 11-866 Radio Receivers BC-779 and Power Supplies RA-74, with fold out schematics, but no covers and kind of ratty. $5 TM 11-4001 Repair Instructions for Radio Receivers BC-312-A through -NX, and BC-342-A through -N, War Dept., 1945. 64 pages. This is not the manual for these radios, just specific repair instructions and schematic excerpts. No covers. $10 Elements of Radio, Signal Corps, Ft. Monmouth, 1942. I believe this is a reprint of Marcus's book but it doesn't say that anywhere. Spine taped, pages dog-eared. $4 Single Sideband Radio Repair, Signal Corps, Ft. Monmouth, 1950. This ocurse is built around servicing an SSB receiver that takes up an entire 6 ft rack. There's many pictures and oversize schematics in a total of about 150 pages. $10 Radio Electronics Part I, Student Notes, Signal Corps, Ft. Monmouth, 1949, about 45 pages. $5 Radio Electronics Part III, Laboratory Notes, Signal Corps, Ft. Monmouth, 1949. This course asks questions which you are expected to answer through lab work on the following radios: SCR-300, SCR-506, SCR-536, SCR-619, etc. But there's no pictures and few schematics. The blanks are not filled in. $7 ANTIQUE WIRELESS ASSOCIATION OLD TIMERS BULLETIN All in excellent condition. $1 each. Minimum order 4 issues. 1983March, June 1992February, August, November 1993February, May,
[AMRadio] HR-10 problem
Hi, I am running an HR-10 RX in my shack outside and am wondering how to cure an annoying fault. Or, this may be bad design, but I don't remember this from when I was a kid. When i turn up the RF Gain, and end up close to full on it, I get a shift down in frequency of the CW note. So far that I have to retune the BFO to get it back. The RF Gain is in series with the Cathode of the first RF stage of the RX. perhaps a Zener diode to cure it? And if so, I guess I should measure the voltage someplace and clamp with a zener, but then again, I would be modifying the whole circut. Anyone know how to fix this? Best 73, Alan
RE: [AMRadio] HR-10 problem
Maybe the tube is out of bias, to much screen voltage, or some resistor has changed value and the LO tube voltage is varying around? Maybe check things with the DMM? Or maybe the bfo is changing, not the LO?? Brett N2DTS -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Monday, April 10, 2006 9:49 AM To: AMRadio@mailman.qth.net Subject: [AMRadio] HR-10 problem Hi, I am running an HR-10 RX in my shack outside and am wondering how to cure an annoying fault. Or, this may be bad design, but I don't remember this from when I was a kid. When i turn up the RF Gain, and end up close to full on it, I get a shift down in frequency of the CW note. So far that I have to retune the BFO to get it back. The RF Gain is in series with the Cathode of the first RF stage of the RX. perhaps a Zener diode to cure it? And if so, I guess I should measure the voltage someplace and clamp with a zener, but then again, I would be modifying the whole circut. Anyone know how to fix this? Best 73, Alan __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] HR-10 problem
You are right, I should be searhing around for some voltage out of spec. 73, Alan Quoting Brett gazdzinski [EMAIL PROTECTED]: Maybe the tube is out of bias, to much screen voltage, or some resistor has changed value and the LO tube voltage is varying around? Maybe check things with the DMM? Or maybe the bfo is changing, not the LO?? Brett N2DTS -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Monday, April 10, 2006 9:49 AM To: AMRadio@mailman.qth.net Subject: [AMRadio] HR-10 problem Hi, I am running an HR-10 RX in my shack outside and am wondering how to cure an annoying fault. Or, this may be bad design, but I don't remember this from when I was a kid. When i turn up the RF Gain, and end up close to full on it, I get a shift down in frequency of the CW note. So far that I have to retune the BFO to get it back. The RF Gain is in series with the Cathode of the first RF stage of the RX. perhaps a Zener diode to cure it? And if so, I guess I should measure the voltage someplace and clamp with a zener, but then again, I would be modifying the whole circut. Anyone know how to fix this? Best 73, Alan __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] HR-10 problem
My HR-10B doesn't do it Alan, so it's not inherent in the design. As Brett suggested, look for voltages that are out of spec. 73, Mark W1EOF -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Monday, April 10, 2006 9:49 AM To: AMRadio@mailman.qth.net Subject: [AMRadio] HR-10 problem Hi, I am running an HR-10 RX in my shack outside and am wondering how to cure an annoying fault. Or, this may be bad design, but I don't remember this from when I was a kid. When i turn up the RF Gain, and end up close to full on it, I get a shift down in frequency of the CW note. So far that I have to retune the BFO to get it back. The RF Gain is in series with the Cathode of the first RF stage of the RX. perhaps a Zener diode to cure it? And if so, I guess I should measure the voltage someplace and clamp with a zener, but then again, I would be modifying the whole circut. Anyone know how to fix this? Best 73, Alan __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.4.0/306 - Release Date: 4/9/06 -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.4.0/306 - Release Date: 4/9/06
[AMRadio] Re: Triode connecting 803's for a Modulator
Elaborating on Don's comment, the reason this is done with the triode-connected 807 is that if the control screen grids were simply tied together, the control grids would be exceeding their maximum dissapation before the screens could be driven hard enough to provide reasonable output. We don't want to vaporize the control grids now, do we :) I suspect this would hold true for other tetrodes pentodes in a triode connection. I've used 6146s as modulators in the triode connection on a couple of occaisions. I feed audio to the screen grids only and just bias the control grid with a DC voltage to set it at the proper operating point. At lower plate voltages (say, 600V or so), the control grids can be tied directly to ground. At higher plate voltage, a few volts negative wrt cathode is all it takes. Screens are at DC ground in either case. Perhaps try something similar with the 803s? 73, -Larry/NE1S Donald Chester writes: I assume all three grids simply strapped together. Is that correct? In some circuits with triode-connected tetrodes, particularly the 807, the screen grids are driven directly with the audio, and a resistor is placed between the screen and control grids.
Re: [AMRadio] Re: Triode connecting 803's for a Modulator
The question was: how to do it with 803's The source listed is the Bill Orr Handbook. He calls all of the circuits Zero Bias Tetrode Modulators. Even the 807 and 813 in TRIODE connection is shown with the beam forming plates grounded. The circuit is about zero bias, and no screen supply. The 803's are shown since they were one very plentiful and cheap. My understanding of the suppressor bias is that it allows the plate voltage to swing down to it and increases both headroom ( work space) and increases efficiency. 510 watts output with clean audio is not bad for zero bias and no screen supply, The suppressor voltage is actually the voltage used on the speech amp plates which is says can be 6B4's or most any 8 watt speech amp. He does say these tube require more drive than 813's but since the then price for a new one was four dollars a tad more drive make little difference. In W6SAI's 14th edition Radio Handbook page 595, chapter 27-3. Seybold's patent no. 2,494,3176 explains the use of beam tetrodes in TRIODE connection to use no bias and no screen supply. The drive is applied to the screens and a resistor to the control grid. The 15th Edition says the grid resistors are not needed for the 803 or 813 tubes.. Hope this helps.. Mike
Re: [AMRadio] FS: Callbooks, Military Manuals, AWA OTB ARC
Hello Donald: If either of the 57/58 Call Books have my old call in it, I will buy same from you. Please look for WN8AGK, Charlie, W.VA. What say OM ?? 73, DE Charlie, K0NG [EMAIL PROTECTED]
RE: [AMRadio] HR-10 problem
I am sure I can find it. Best 73 Alan Quoting W1EOF [EMAIL PROTECTED]: My HR-10B doesn't do it Alan, so it's not inherent in the design. As Brett suggested, look for voltages that are out of spec. 73, Mark W1EOF -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Monday, April 10, 2006 9:49 AM To: AMRadio@mailman.qth.net Subject: [AMRadio] HR-10 problem Hi, I am running an HR-10 RX in my shack outside and am wondering how to cure an annoying fault. Or, this may be bad design, but I don't remember this from when I was a kid. When i turn up the RF Gain, and end up close to full on it, I get a shift down in frequency of the CW note. So far that I have to retune the BFO to get it back. The RF Gain is in series with the Cathode of the first RF stage of the RX. perhaps a Zener diode to cure it? And if so, I guess I should measure the voltage someplace and clamp with a zener, but then again, I would be modifying the whole circut. Anyone know how to fix this? Best 73, Alan __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.4.0/306 - Release Date: 4/9/06 -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.4.0/306 - Release Date: 4/9/06 __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
[AMRadio] TRIM CLIPS
LOOKING FOR THE WIRE TRIM CLIPS ON A NC300 OR 303 ANY OLD JUNKERS LAYING AROUND
[AMRadio] DX100
Hi, Recently picked up a DX100 with the entire modulation section gone. Have the parts to rebuild with the exception of the modulation transformer. Anybody got one to sell or trade or know where same may be purchased? Bill WD4HEN From [EMAIL PROTECTED] Mon Apr 10 21:10:51 2006 Return-Path: [EMAIL PROTECTED] X-Original-To: amradio@mailman.qth.net Delivered-To: amradio@mailman.qth.net Received: from wmail-0.airmail.net (wmail-0.airmail.net [209.196.70.87]) by mailman.qth.net (Postfix) with ESMTP id 0EC93859C1F for amradio@mailman.qth.net; Mon, 10 Apr 2006 21:10:51 -0400 (EDT) Received: from 66-90-210-150.dyn.grandenetworks.net ([66.90.210.150] helo=airmail.net) by wmail-0.airmail.net with esmtpa (Exim 4.60) (envelope-from [EMAIL PROTECTED]) id 1FT7OV-0002pX-Eh for amradio@mailman.qth.net; Mon, 10 Apr 2006 20:10:12 -0500 Message-ID: [EMAIL PROTECTED] Date: Mon, 10 Apr 2006 20:10:23 -0500 From: Rick Brashear [EMAIL PROTECTED] User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Discussion of AM Radio amradio@mailman.qth.net Subject: Re: [AMRadio] DX100 References: [EMAIL PROTECTED] In-Reply-To: [EMAIL PROTECTED] Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: amradio@mailman.qth.net X-Mailman-Version: 2.1.4 Precedence: list Reply-To: Discussion of AM Radio amradio@mailman.qth.net List-Id: Discussion of AM Radio amradio.mailman.qth.net List-Unsubscribe: http://mailman.qth.net/mailman/listinfo/amradio, mailto:[EMAIL PROTECTED] List-Archive: http://mailman.qth.net/mailman/private/amradio List-Post: mailto:amradio@mailman.qth.net List-Help: mailto:[EMAIL PROTECTED] List-Subscribe: http://mailman.qth.net/mailman/listinfo/amradio, mailto:[EMAIL PROTECTED] X-List-Received-Date: Tue, 11 Apr 2006 01:10:51 - Bill, I may have one in the shed. I can't remember if the parts rig out there is a DX-1 or DX-100. I'll check in the morning. If you haven't heard back soon, please, remind me, I'm old and forgetful. Rick/K5IZ Bill Campbell wrote: Hi, Recently picked up a DX100 with the entire modulation section gone. Have the parts to rebuild with the exception of the modulation transformer. Anybody got one to sell or trade or know where same may be purchased? Bill WD4HEN __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] Re: Triode connecting 803's for a Modulator
I was thinking that I had read an article published by RCA explaining that the series grid resistor on 807/1625s, 20K as I recall, was placed in circuit for linearity reasons. It was having something to do with a dip or a peak in transconductance mid way in the drive. The solution was simple but it did not come to the engineers right away. Does anyone else remember the article or am I just imagining it, age you know does funny things? Of course it would protect the grid as well but I was thinking it was mainly for linearity. John, WA5BXO -Original Message- On Behalf Of ne1s Sent: Monday, April 10, 2006 12:04 PM Subject: [AMRadio] Re: Triode connecting 803's for a Modulator Elaborating on Don's comment, the reason this is done with the triode-connected 807 is that if the control screen grids were simply tied together, the control grids would be exceeding their maximum dissapation before the screens could be driven hard enough to provide reasonable output. We don't want to vaporize the control grids now, do we :) I suspect this would hold true for other tetrodes pentodes in a triode connection.
RE: [AMRadio] Triode connecting 803's for a Modulator
Thank you for the detailed information. I appreciate it. My friend is sending me copies of the Handbook article. It is great to have a responsive group like this with so much knowledge on tap. 73, Bob K2GLO
