20070618.ba v04_n060.bam.20070618 >From ???@??? Mon Jun 18 14:56:10 2007 -0500 Date: Mon, 18 Jun 2007 19:55:19 GMT From: Old Tube Radios To: Old Tube Radios Subject: BOATANCHORS digest 4060 Message-Id: <20070618195523.DE16947011E@srvr1.theporch.com> BOATANCHORS Digest 4060 Topics covered in this issue include: 1) Racal RA17-C12 Receiver RA 17 C 12 by "Herbert M. Rosenthal" 2) Re: Racal RA17-C12 Receiver RA 17 C 12 by 3) RE: Racal RA17-C12 Receiver RA 17 C 12 by "Ed Sieb" 4) How far to go with a 30's power transformer? by "John Gillespie" 5) Re: Racal RA17-C12 Receiver RA 17 C 12 by "John Gillespie" 6) RACAL RA17-C12 Receiver by "Herbert M. Rosenthal" 7) Re: How far to go with a 30's power transformer? by "Arden Allen" 8) Re: damaged ferrite slugs by "Arden Allen" 9) Midland SWR bridge. by "Ken" 10) Question, G.E. Model JK-70 Receiver by Mike 11) Re: Question, G.E. Model JK-70 Receiver by stuck in 50s 12) OT, but Outstanding. by "David's Mail" 13) RE: OT, but Outstanding. by "Grant Youngman" 14) RE: OT, but Outstanding. by "J.D. Mac Aulay, WQ8U" 15) For Sale by Mike 16) Lost e-mail archives - Old Tube Radios by "Art Lebermann" 17) "Magazine management" tip.... by john 18) For Sale: Test Equipment, Antique Radios and Misc. by David Hollander 19) Manual and Power Cord Wiring Diagram needed For Squires Sanders IBS Receiver by Jim Allen 20) RF Comm RF-301 Radio Problems by David Hollander 21) KPH visit by "Arden Allen" 22) Weirdo! by "Ken" 23) RE: Weirdo! by "James C. Garland" <4cx250b@muohio.edu> ---------------------------------------------------------------------- Message-ID: <466CF0EA.9000306@comcast.net> Date: Mon, 11 Jun 2007 00:51:22 -0600 From: "Herbert M. Rosenthal" MIME-Version: 1.0 To: Old Tube Radios Subject: Racal RA17-C12 Receiver RA 17 C 12 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit One of these in 'excellent condition' sold for $311-all 92.5 pounds of it-today. Good price or giveaway? Herb W5AN # 260125287880 ------------------------------ Message-ID: <17494.65.218.135.67.1181566283.squirrel@samson.email.starband.net> Date: Mon, 11 Jun 2007 08:51:23 -0400 (EDT) Subject: Re: Racal RA17-C12 Receiver RA 17 C 12 From: To: Old Tube Radios Cc: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit I think $311 was an extremely good price for an RA-17C in excellent condition. I like those receivers, I have two. In fact I had my older one since 1969. 73, Meir WF2U Landrum, SC > One of these in 'excellent condition' sold for $311-all 92.5 pounds of > it-today. Good price or giveaway? > Herb W5AN > # 260125287880 ------------------------------ From: "Ed Sieb" To: Old Tube Radios Cc: "Old Tube Radios" , Subject: RE: Racal RA17-C12 Receiver RA 17 C 12 Date: Mon, 11 Jun 2007 09:09:33 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Up here, those receivers typically command about $400.-$450. (Canadian $$, which is almost par now). Ed, VA3ES -----Original Message----- From: owner-boatanchors@theporch.com [mailto:owner-boatanchors@theporch.com]On Behalf Of wf2u@starband.net Sent: Monday, June 11, 2007 8:51 AM To: Old Tube Radios Cc: herbrose@comcast.net Subject: Re: Racal RA17-C12 Receiver RA 17 C 12 I think $311 was an extremely good price for an RA-17C in excellent condition. I like those receivers, I have two. In fact I had my older one since 1969. 73, Meir WF2U Landrum, SC > One of these in 'excellent condition' sold for $311-all 92.5 pounds of > it-today. Good price or giveaway? > Herb W5AN > # 260125287880 ------------------------------ Message-ID: <000501c7ac2a$a55d2f60$fa31bb40@k9a1e1> From: "John Gillespie" To: Old Tube Radios Subject: How far to go with a 30's power transformer? Date: Mon, 11 Jun 2007 09:15:53 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit Heres a question...... I am restoring a 1930/31 Deforest Crosley, replaced the caps., rebuilt the old wet electrolytics using new electrolytics inside and returned them to the chassis. Replaced all the old out of spec resistors, which in this set is basically all of them. Now I am down to the power and output transformers. The original wiring is part cloth covered and part rubber insulated. The cloth covered is all hard and dry and not too much of an issue if left alone, but the old rubber insulated is so dried out its basically like brittle bakelite, one touch, and its falling to pieces. My concern is where the wires come through the chassis. Originally, Deforest used a thick rubber sleeve and now its like glass. Whats the general concensus? For safety sake, I think I should either 1/ Uunsolder the loose ends, break off all the old insulation and replace with a new coating of spagetti or plastic tubing? OR 2/ Remove the transformers whole and replace all the wiring at the core? Not faint of heart, or work shy, but what would you guys do? ......john ------------------------------ Message-ID: <000801c7ac2b$05e95f20$fa31bb40@k9a1e1> From: "John Gillespie" To: Old Tube Radios Cc: "old tube radios" Subject: Re: Racal RA17-C12 Receiver RA 17 C 12 Date: Mon, 11 Jun 2007 09:18:36 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit $311, is a fantastic price IMO. I would have broken my wrist getting my wallet out of my pocket, hihi.. Subject: Re: Racal RA17-C12 Receiver RA 17 C 12 > > One of these in 'excellent condition' sold for $311-all 92.5 pounds of > > it-today. Good price or giveaway? ------------------------------ Message-ID: <466D60E9.1080302@comcast.net> Date: Mon, 11 Jun 2007 08:49:13 -0600 From: "Herbert M. Rosenthal" MIME-Version: 1.0 To: Old Tube Radios Subject: RACAL RA17-C12 Receiver Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Well, I was tempted to buy it; $$ not an object. I tracked it for the week it was up for auction. I agonized whether to 'upsize' here in my limited-sized ham shack/computer room, having downsized a few years back, and decided not to bring this humongus receiver into our rather small home. Sure wish I had a basement to work in, or to set up a larger shack, but I'm satisfied that I have what I have-a 100w Yaesu FT840, a DSP from Timewave, an antenna tuner from LDG and a 2M xceiver. Good for rag chewing in CONUS plus an occasional dx contact. Beats a poke in the eye. I was tempted to post a reference here on BA so that someone without room constraint might get it, but as I understand it, that's a nono. Next time I see something like this, I'll post a 'contact me for info' msg; this should be OK with the boss :-). Oh, yes, the RX was in Vancouver and the seller estimated $100 for shipping, but still a reasonable price. Herb W5AN Albuquerque ------------------------------ Message-ID: <003201c7ac49$75146750$08a1480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: How far to go with a 30's power transformer? Date: Mon, 11 Jun 2007 09:56:19 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit John, what do do. I have done a variety of things including what you mentioned. Cloth wiring that is intact and has at least a little flexibility I usually either treat with WD-40 (brushed on) or thinned laquer. It's a judgement call as to which approach is better for extended safe service life. Glassified rubber that is not likely to be moved will get a couple of coats of laquer. The rest will get replaced with modern PVC insulated hookup wire of the same gauge and color. In the case of power transformers I have had to replace spaghetti on magnet wire leads where the old has turned to powder. I've had to remove transformers and relead them where the leads are too badly deteriorated to be trusted inside the transformer. It's partly an appearance issue too. I also apply WD-40 to old transformers to help seal out moisture. The choice of WD-40 (or equivalent product) is for its penetration capability as well as its insulating property. Magnet wire insulation in ancient transformers is very fragile and the only thing that keeps a tranformer from failing is relatively low voltage gradients between turns and layers. I believe the light oil helps to replace the function of cracked and displaced magnet wire insulation by sealing out air. It's only a theory and there may be a detriment to such a practice so use your own judgement. Arden Allen KB6NAX ------------------------------ Message-ID: <000d01c7ac63$29801c70$64a0480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: damaged ferrite slugs Date: Mon, 11 Jun 2007 13:00:22 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit On further thought.... It was mentioned that the application of heat can free a stuck slug. Heat can work to free slugs in paper based or phenolic coil forms but not in plastic coil forms as the plastic will soften and effectively weld the slug in place. If a slug is not broken but just stuck in place due to the adhesive effect of coil form impregnant acetone can free up the slug. Arden Allen KB6NAX ------------------------------ Message-ID: <000501c7ad07$4c16fde0$6b9c1f45@rtconline.com> From: "Ken" To: Old Tube Radios Subject: Midland SWR bridge. Date: Tue, 12 Jun 2007 08:35:24 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Hi Gang, Does anyone have data on the Midland model 23-126 SWR meter? A schematic with parts values would be a big help. Thanks & take care, Ken N5CM ------------------------------ Date: Wed, 13 Jun 2007 14:16:41 -0700 From: Mike Subject: Question, G.E. Model JK-70 Receiver To: Old Tube Radios Message-id: <000b01c7ae00$231c03a0$6501a8c0@m0a1da7d341114> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original Content-transfer-encoding: 7bit I'm restoring a G.E. wooden case table top radio, vintage circa 1940, model JK-70. It's a pretty standard tube line-up with what amounts to one IF stage, one tube and two transformers in the IF strip. I know it's considered "cheating" but I'm using a schematic from a CD that might be a scan of a Canadian Radio College volume page. Now the fun begins. The second IF transformer output coil/cap tabs are not connected to anything (if the letters on the schematic and transformer base are accurate) and there's no sign they've ever received solder. The radio shows signs of having been repaired at least once. The schematic indicates the two IF transformers are similar if not exactly the same. The first one has connections that make sense and that follow the schematic. The radio plays and appears normal after replacing a couple of leaky caps and a burned resistor. (Result of one leaky cap) I haven't done any sensitivity checks but top and bottom slugs in both IF transformers respond to aligning just like the alignment directions say they should. So what gives? Mike VE7MMH ------------------------------ Date: Thu, 14 Jun 2007 09:43:19 -0400 (EDT) From: stuck in 50s Message-Id: <200706141343.l5EDhJUB015510@fracas.netboobie.org> To: Old Tube Radios Subject: Re: Question, G.E. Model JK-70 Receiver Mike could it be only the primary was used for the IF tube's plate. Same was then capacity copupled to the 2nd detector diode. Was perhaps a serviceman's kludge to make-do with an on-hand interstage IFT when original output IFT's primary had gone open ckt. You say it works. Do BOTH slugs on subject IF transformer affect resonance (alignment)? If both afffect it strongly, you've got one for the books. Otherwise kludge guess probably right. Marty ------------------------------ Message-ID: <003301c7aecc$7d0db440$6401a8c0@boudreaux> From: "David's Mail" To: Old Tube Radios Subject: OT, but Outstanding. Date: Thu, 14 Jun 2007 16:38:45 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_002A_01C7AEA2.79CBC1C0" This is a multi-part message in MIME format. ------=_NextPart_000_002A_01C7AEA2.79CBC1C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Who said hams can't invent world-changing=20 things anymore?? http://www.evtv1.com/player.aspx?itemnum=3D8159 Now if I can just figure out what freq he was using.... ------=_NextPart_000_002A_01C7AEA2.79CBC1C0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ---REMAINDER OF MESSAGE TRUNCATED--- * * This post contains a forbidden message format * * (such as an attached file, a v-card, HTML formatting) * * Mail Lists at theporch.com only accept PLAIN TEXT * * If your postings display this message your mail program * * is not set to send PLAIN TEXT ONLY and needs adjusting * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ------=_NextPart_000_002A_01C7AEA2.79CBC1C0-- ------------------------------ From: "Grant Youngman" To: Old Tube Radios Subject: RE: OT, but Outstanding. Date: Thu, 14 Jun 2007 17:51:55 -0500 Message-ID: <005201c7aed6$9bdaa360$6601a8c0@GYGateway> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit The real question of course, is whether the energy output of this thing exceeds the energy input required to run the RF generator ... Grant/NQ5T > -----Original Message----- > From: owner-boatanchors@theporch.com > [mailto:owner-boatanchors@theporch.com] On Behalf Of David's Mail > Sent: Thursday, June 14, 2007 4:39 PM > To: Old Tube Radios > Subject: OT, but Outstanding. > > Who said hams can't invent world-changing > things anymore?? > > http://www.evtv1.com/player.aspx?itemnum=8159 > > Now if I can just figure out what freq he was using.... > ------------------------------ Date: Thu, 14 Jun 2007 19:23:55 -0700 (PDT) From: "J.D. Mac Aulay, WQ8U" Subject: RE: OT, but Outstanding. To: Old Tube Radios MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-1335051249-1181874235=:19830" Content-Transfer-Encoding: 8bit Message-ID: <260331.19830.qm@web54602.mail.re2.yahoo.com> --0-1335051249-1181874235=:19830 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Now, now now.... We can't let the basic laws of physics and simple business mathematics interfere with our progressive thinking - after all, we are going to save the world from ________ (enter your choice). Let's see, the transmitter is inefficient, the antenna is inefficient, the medium interaction is inefficient, the thermal transfer to the engine is inefficient, and, of course, the engine is inefficient. The interesting test would be to hook the engine to a generator (also inefficient) and see if it could power the transmitter. Any bets on how long it would run, if at all? 73 Mac WQ8U Hillsborough, NC Grant Youngman wrote: The real question of course, is whether the energy output of this thing exceeds the energy input required to run the RF generator ... Grant/NQ5T > -----Original Message----- > From: owner-boatanchors@theporch.com > [mailto:owner-boatanchors@theporch.com] On Behalf Of David's Mail > Sent: Thursday, June 14, 2007 4:39 PM > To: Old Tube Radios > Subject: OT, but Outstanding. > > Who said hams can't invent world-changing > things anymore?? > > http://www.evtv1.com/player.aspx?itemnum=8159 > > Now if I can just figure out what freq he was using.... > --0-1335051249-1181874235=:19830 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ---REMAINDER OF MESSAGE TRUNCATED--- * * This post contains a forbidden message format * * (such as an attached file, a v-card, HTML formatting) * * Mail Lists at theporch.com only accept PLAIN TEXT * * If your postings display this message your mail program * * is not set to send PLAIN TEXT ONLY and needs adjusting * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * --0-1335051249-1181874235=:19830-- ------------------------------ Date: Fri, 15 Jun 2007 07:38:14 -0700 From: Mike Subject: For Sale To: Old Tube Radios Message-id: <000801c7af5a$ceb5b200$6501a8c0@m0a1da7d341114> MIME-version: 1.0 Content-type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original Content-transfer-encoding: 7bit Moving causes the following for sale: 1. BC-610E/614E/939 $500 2. Johnson Thunderbolt $300 For details contact mike46@shaw.ca Mike VE7MMH ------------------------------ Message-ID: <3BABF1ACA47741D2861E173D2F3E2378@ArthurPC> From: "Art Lebermann" To: Old Tube Radios Subject: Lost e-mail archives - Old Tube Radios Date: Fri, 15 Jun 2007 20:38:45 -0700 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit My PC crashed, and my archived e-mail has been lost. I've been in contact with several members of the "Old Tube Radios" list, on various subjects, and now need your help to get back in touch. If you wondered where I went - now you know! Drop me a note, and I'll get you back in my address book. Thanks! Art Lebermann W6REQ artleb@earthlink.net Transmitter Engineer KGO / KSFO / KMKY ABC Radio San Francisco ------------------------------ Message-Id: <6.2.1.2.2.20070616091625.030225f0@pop-server.nc.rr.com> Date: Sat, 16 Jun 2007 09:22:06 -0400 To: Old Tube Radios From: john Subject: "Magazine management" tip.... Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed The small, narrow priority mail boxes ......in USPS jargon: Priority Mail Large Video Box (O-1096L) Make fine storage boxes for Electric Radio, and OTB format magazines. 30 seconds will leave you with a perfect storage box for one years worth. Available free at your local USPS, or open your packages carefully to recycle them into magazine holders. John K5MO ------------------------------ Message-ID: <46743A7A.3080008@cox.net> Date: Sat, 16 Jun 2007 12:31:06 -0700 From: David Hollander MIME-Version: 1.0 To: Old Tube Radios Subject: For Sale: Test Equipment, Antique Radios and Misc. Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Here are some items for sale. Prices do not include shipping. I will ship overseas. Heathkit QM-1 Q-Meter with Manual................$85 plus shipping This is a working unit. Includes a photocopy of the manual. http://members.cox.net/radiodx3/heath_qmeter.JPG Marconi AM/FM Signal Generator Model TF 995A.........$100 plus shipping Covers from 1.5 to 220 Mc/s in five bands. Its open circuit output level is variable in 1 db steps, from a minimum of 0.1 micro volts to a maximum of 100 mV at 52 ohms and 200 mV at 75 ohms. The output may be CW,, frequency modulated, amplitude modulated, or simultaneously both frequency and. amplitude modulated.The unit works. I was able to hear the signal at various frequencies on a a general coverage receiver. It may need calibration. The power cord and test lead are tucked into the side of the unit. No manual. Heavy unit/ http://members.cox.net/radiostuff9/marconi_siggen.JPG Radio Craftsmen Model 10 AM-FM Tuner with Manual......$80 plus shipping This is a 12 tube chrome chassis mono unit from around 1950. This unit works very well. I hooked it up to a dual 6V6 mono amp and a 15 inch speaker and let it play while I was working in my shop. It sounds very good on both the am and fm broadcast that I listened to and all controls do what they are supposed to do. If you like playing with vintage mono units, this unit would be a nice unit to play with. Includes an 8 page Rider's manual http://members.cox.net/radiodx5/craftsman_tuner.JPG http://members.cox.net/radiodx5/craftsman_tuner2.JPG Dumont Type 346 AC Compact Voltmeter.........$20 plus shipping This is a compact unit that will measure ac voltage from 0.001 volts to 300 volts in 12 ranges. This is a compact unit measuring 4 inches wide by 6 inches high by 7 inches deep. This is a tested working unit in excellent condition. The input jacks fit standard banana type plus. http://members.cox.net/radiostuff9/dumont_acvoltmeter.JPG Philco 42-327 BC/SW Radio...........$25 plus shipping Project radio. Appears complete (except power cord) http://members.cox.net/radiodx3/philco_42_327.JPG http://members.cox.net/radiodx3/philco_42_3272.JPG http://members.cox.net/radiodx3/philco_42_3273.JPG 12 Tube 1930's "Unknown Brand" Radio...............$40 plus shipping 1930's radio of unknown origin. This radio has a high tube count however a number of the tubes are just ballast tubes. The extra tubes were added to the radio to impress the public with the high tube count. This radio covers the AM broadcast band and one short wave band covering 2.2 to 7 MC. The radio is restorable. The wooden case is in reasonably good condition with some veneer missing on the bottom left. The radio is missing several tubes and the knobs. Reproduction plastic dial covers are available from a number of sources. http://members.cox.net/radiostuff9/30s_radio.JPG http://members.cox.net/radiostuff9/30s_radio3.JPG http://members.cox.net/radiostuff9/30s_radio4.JPG Large National Radio Ceramic Coil Forms.........$14 plus shipping These are 2.5 inches in diameter. http://members.cox.net/radiodx3/ceramic_coilsx2.JPG 73 and thanks for looking. -- *********************************************************** Dave N7RK Boatanchors Home Page: http://members.cox.net/n7rk Phoenix, Arizona *DXCC Honor Roll* *WAZ#22 - 75 Meter SSB* ex-XE2/N7RK, N7RK/ZB2, VK2ERK, ZM0AJN, WB6NRK, WN6IWX Boatanchor and Antique Radio Collector ------------------------------ Date: Sat, 16 Jun 2007 14:13:23 -0700 (PDT) From: Jim Allen Subject: Manual and Power Cord Wiring Diagram needed For Squires Sanders IBS Receiver To: Old Tube Radios MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-405758078-1182028403=:9122" Message-ID: <765142.9122.qm@web82610.mail.mud.yahoo.com> --0-405758078-1182028403=:9122 Content-Type: text/plain; charset=ascii Hi, I'm in desparate need of a manual and instructions for wiring the power cord for a Squires Sanders IBS receiver. Anyone out there that can help? Thanks, Jim NU6AM --0-405758078-1182028403=:9122 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ---REMAINDER OF MESSAGE TRUNCATED--- * * This post contains a forbidden message format * * (such as an attached file, a v-card, HTML formatting) * * Mail Lists at theporch.com only accept PLAIN TEXT * * If your postings display this message your mail program * * is not set to send PLAIN TEXT ONLY and needs adjusting * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * --0-405758078-1182028403=:9122-- ------------------------------ Message-ID: <46745461.1000002@cox.net> Date: Sat, 16 Jun 2007 14:21:37 -0700 From: David Hollander MIME-Version: 1.0 To: Old Tube Radios Subject: RF Comm RF-301 Radio Problems Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hello...is anyone on the list familiar with the RF Comm (Harris) RF-301 as in worked on one or done some troubleshooting on one of these radios? Need some help if you are familiar with this radio. 73 es Tnx, Dave N7RK -- *********************************************************** Dave N7RK Boatanchors Home Page: http://members.cox.net/n7rk Phoenix, Arizona *DXCC Honor Roll* *WAZ#22 - 75 Meter SSB* ex-XE2/N7RK, N7RK/ZB2, VK2ERK, ZM0AJN, WB6NRK, WN6IWX Boatanchor and Antique Radio Collector ------------------------------ Message-ID: <001701c7b111$0e16e3d0$6f9e480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: KPH visit Date: Sun, 17 Jun 2007 11:54:46 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit BA'ers, Saturday I enjoyed meeting Dick Dillman, Steve Hawes and Denice Stoops at the KPH transmitting station near Bolinas, CA. They are delightful folks to know and I admire them for their unswerving dedication to preserving the history and practices of a few of our radio antecedents. The morning started off meeting the crew and enjoying fresh coffee and sweet rolls. That began my trip into some radio history I won't forget as the crew toured me through the transmitter and operating rooms. Now the dinasaurs of shortwave communication the great old transmitters are still being heard by a faithful few around the world. Then I followed Dick as he went up the coast to the Point Arena receiving site to begin the day's operating while I delightedly examined more equipment. That's where Dick gave me a comprehensive history lesson about the personalities that operated and maintained the stations during the heydays of global ship to shore and point to point radio and its eventual demise at the hands of aerospace technology. There's quite a story to be revealed by a visit to KPH so I urge folks to visit the station when in the San Francisco area. Many thanks to Dick and the gang. The Maritime Radio Historical Society website is www.radiomarine.org. Arden Allen KB6NAX ------------------------------ Message-ID: <000901c7b1c9$fe4dc180$6b9c1f45@rtconline.com> From: "Ken" To: Old Tube Radios Subject: Weirdo! Date: Mon, 18 Jun 2007 09:59:10 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Fellows, Here is one for the books! I don't begin to try to explain it. You figgure it out! My Midland Model 23-126 Standing Wave Bridge quit reading reflected power! In "Forward" it adjusts ok but when I switch to "Reflected" the needle goes to about midscale and remains there regardless. I discovered by experimenting, that in Forward if I dipped the two tuning condensers on the Johnson Antenna Tuner, not the KW model, the signal reported was good, best I had been getting. By bringing the needle up with the adjust potentiometer and then dipping, stations report my signal up and good. The transmitter is a Central Electronics 100V. Reminds me of "dipping the final plate on an amplifier". Something in the SWR Bridge circuit has changed that results in this weird effect I presume. It is not acting like a field strength meter which you would tune for maximum reading! Puzzled! Take care, Ken N5CM ------------------------------ From: "James C. Garland" <4cx250b@muohio.edu> To: Old Tube Radios Subject: RE: Weirdo! Date: Mon, 18 Jun 2007 09:24:53 -0600 Message-ID: <003f01c7b1bc$d288d7e0$06e83586@Garland> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi Ken, You probably have a bad detector diode in the reverse power part of your SWR bridge. Th Midland unit is just a simple reflectometer, as I recall, and most likely used Ge diodes to pick off the forward and reverse voltage. The "dipping" you see in the forward position probably means that when you tune your Matchbox to resonance, you're minimizing the impedance, thus causing the forward voltage reading to drop. I doubt you'd see the same thing with other antennas. 73, Jim W8ZR ********************** Jim Garland W8ZR Santa Fe, NM www.w8zr.net ********************* -----Original Message----- From: owner-boatanchors@theporch.com [mailto:owner-boatanchors@theporch.com] On Behalf Of Ken Sent: Monday, June 18, 2007 10:59 AM To: Old Tube Radios Subject: Weirdo! Fellows, Here is one for the books! I don't begin to try to explain it. You figgure it out! My Midland Model 23-126 Standing Wave Bridge quit reading reflected power! In "Forward" it adjusts ok but when I switch to "Reflected" the needle goes to about midscale and remains there regardless. I discovered by experimenting, that in Forward if I dipped the two tuning condensers on the Johnson Antenna Tuner, not the KW model, the signal reported was good, best I had been getting. By bringing the needle up with the adjust potentiometer and then dipping, stations report my signal up and good. The transmitter is a Central Electronics 100V. Reminds me of "dipping the final plate on an amplifier". Something in the SWR Bridge circuit has changed that results in this weird effect I presume. It is not acting like a field strength meter which you would tune for maximum reading! Puzzled! Take care, Ken N5CM ------------------------------ End of BOATANCHORS Digest 4060 ******************************