20090601.ba v04_n271.bam.20090601 >From ???@??? Mon Jun 1 00:00:39 2009 -0500 Date: Mon, 1 Jun 2009 00:00:03 CST From: Old Tube Radios To: Old Tube Radios Subject: BOATANCHORS digest 4271 Message-Id: <20090601060005.95DEF10B069@srvr1.theporch.com> BOATANCHORS Digest 4271 Topics covered in this issue include: 1) RME 4350 Help! by Daniel Wright 2) Re: How Does The AN Nomenclature System Work? by "Arden Allen" 3) Re: How Does The AN Nomenclature System Work? by John Oglesby 4) Re: How Does The AN Nomenclature System Work? by Jerry Proc 5) HF Aircraft Antennas by Jerry Proc 6) Re: RME 4350 Help! by wb3fau@att.net 7) Re: HF Aircraft Antennas by AAFRadio 8) Two Questions by "Michael Hardie" 9) Re: Two Questions by Gary Woods 10) Re: Two Questions by Scott Robinson 11) Re: HF Aircraft Antennas by "Arden Allen" 12) Re: Two Questions by "Arden Allen" 13) Re: HF Aircraft Antennas by "Arden Allen" 14) Re: HF Aircraft Antennas by Dan Arney ---------------------------------------------------------------------- Message-ID: <4A21A609.1060400@neb.rr.com> Date: Sat, 30 May 2009 16:32:57 -0500 From: Daniel Wright MIME-Version: 1.0 To: Old Tube Radios Subject: RME 4350 Help! Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Greetings! I just acquired a very very nice RME 4350 (not "A"). It is just beautiful, but is also pretty deaf. I checked the tubes and found a couple of marginal ones that made a marginal improvement. The S meter barely moves off the peg and the signals I do hear are weak. I know the radio has been.....what?...."restored"? Or at least re-capped somewhat. The antenna terminal strip has been replaced with an SO-239, very very nicely done. I would love to get this beautiful rig up and running correctly. Are there any RME experts on the list? I have the owners manual, but it's pretty sparse on details. Is there a service manual? Is there a SAMS photofact on this rig? ANY help would be greatly appreciated!!! Thanks much es 73 de Dan -- WAØJRD .. dwright12@neb.rr.com ------------------------------ Message-ID: <000d01c9e179$b88f6ef0$469e480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: How Does The AN Nomenclature System Work? Date: Sat, 30 May 2009 15:54:31 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit > Does anyone know the inner workings of the AN/Nomenclature system? I'm sure it's a system that goes by the rule that states that problems will be solved by creating exceptions to the rules. Arden Allen KB6NAX Adopt a shelter dog, save an innocent life, and make a friend forever =:-) ------------------------------ Message-ID: <4A21BDF7.2070809@charter.net> Date: Sat, 30 May 2009 19:15:03 -0400 From: John Oglesby MIME-Version: 1.0 To: Old Tube Radios CC: Old Tube Radios Subject: Re: How Does The AN Nomenclature System Work? Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Jerry - I can only vouch for the US system, but in short. A company gets a contract from the US Gov. to design a unit to a specification. It could be at the system or black box level. As part of that contract, there must be a "data item deliverable" requested by the Gov for the contractor to submit a request for nomenclature. Companies try really hard to get this included as it is a key to future sales. The Navy assigns all of the nomenclatures for the services based on a mil-spec - I don't remember the number. The only way to get an official nomenclature is through this process as part of a contract. You could also be a subcontractor that is building a receiver, or other item, and that would likely have a sub-nomenclature. For instance a GRC-206 has a raft of R/T's with separate nomenclatures, like the UHF/VHF RT-1319 manpack transceiver. Sometimes manufacturers will give their design a self assigned pseudo-nomenclature. Motorola was good at that at one time. But this doesn't go over well with US customers. It is mostly useful for foreign sales. The design is owned by the "design authority". Typically this is the original designer, although occasionally the government will take over, but it is almost always late in the life cycle of the unit. Usually in the sustainment phase (end of life). There is no central authority of any type. The government may, or may not, decide to buy data rights to the design. If they do, then they can have other companies build to the original design, but it is not commonly done. It is really hard to get a design to stand still long enough to have a second source workout well. It has to be something that is design stable and they want to buy a lot of them, over a relatively long period of time. Or, more commonly, they are mad at the original contractor, or think they are being overcharged. They need some motivation because it is a lot of work and risky as well. History is littered with examples of failed second sources. The last major radio second source was SINCGARS, it didn't work out too well. At one time there was an effort in the Navy to certify and validate data packages. The idea being that they would build to the drawings to prove they were adequate to duplicate the original manufactures results. Maybe a good idea, but it was just used twice (the YUK-14 airborne computer and the last being the Collins ARC-182) and ended up costing more than a single source. This was different during WWII. The government seized designs based on emergency powers and companies cooperated in spirit of the times. That was why there were so many builders of WWII gear. During the 50's and 60's designs lasted a long time - like the VRC-12 - which was in production for about 30 years. The designs were very mature and proven. It was easy to get another source qualified. Not so today. Designs are short lived and changing quickly, particularly in communications. It mirrors the commercial market. A design doesn't last long enough to justify the time and effort to get another source qualified. This is just the tip of the iceberg on this topic. There are lots of subtleties in this subject and a lot of lawyers have gotten rich arguing about who owns what and what can or can not be shared with other contractors. I can expound on this topic at length as this is a big part of building radios for the government. So I will quit before you all fall asleep. 73 John N9RE The contrJerry Proc wrote: > Hello List Members, > > Does anyone know the inner workings of the AN/Nomenclature system? > Take the AN/URR-35 UHF receiver as an example. In Canada, this recevier was built for the Royal Canadian Navy by Cossor Electronics and also by Canadian Westinghouse. I'm fairly certain that other manufacturers made the URR-35 for the USN. > > Who then, owns the actual receiver design? Is it the company who is awarded the first contract? If the military wants to source the device to a second supplier must the design be shared by the company who was awarded the first contract? Is there some central authority who owns the designs/specifications or does the AN system force the designs to be shared? > > Can any manufacturer apply for an AN/designator for their equipment or must there be a contract in place with the military? > > > -- > Regards, > Jerry Proc > E-mail: jerry7proc@yahoo.com > > > __________________________________________________________________ > Yahoo! Canada Toolbar: Search from anywhere on the web, and bookmark your favourite sites. Download it now > http://ca.toolbar.yahoo.com. > > ------------------------------ Message-ID: <680215.14624.qm@web90604.mail.mud.yahoo.com> Date: Sun, 31 May 2009 09:54:15 -0700 (PDT) From: Jerry Proc Subject: Re: How Does The AN Nomenclature System Work? To: Old Tube Radios Cc: Old Tube Radios MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Hi John, Thank you for you detailed reply and to the others who responded so far.=20 The crushing complexity should not come as any surprise when it comes to de= aling with the procurement of gear for the military.=20 As a side comment, here in Canada we have now set and surpassed the record = for the *longest* military procurement in the whole world. The replacement= of our 1962 vintage Sea King helicopters started in 1980. A contract was s= igned about 2 years ago with Sikorsky and deliveries ought to start around = 2012 but that's assuming there are no problems. -- Regards, Jerry Proc E-mail: jerry7proc@yahoo.com --- On Sat, 5/30/09, John Oglesby wrote: > From: John Oglesby > Subject: Re: How Does The AN Nomenclature System Work? > To: "Old Tube Radios" > Cc: "Old Tube Radios" > Received: Saturday, May 30, 2009, 4:15 PM > Jerry - I can only vouch for the US > system, but in short. >=20 > A company gets a contract from the US Gov. to design a unit > to a specification.=A0 It could be at the system or black > box level. >=0A=0A=0A ___________________________________________________________= _______=0ALooking for the perfect gift? Give the gift of Flickr! =0A=0Ahttp= ://www.flickr.com/gift/ ------------------------------ Message-ID: <249747.72277.qm@web90601.mail.mud.yahoo.com> Date: Sun, 31 May 2009 10:54:42 -0700 (PDT) From: Jerry Proc Subject: HF Aircraft Antennas To: Old Tube Radios MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Hello Everyone, As I drill down deeper into the Avenger electronics, I discovered a drawing error. Before contacting the author of the book, I need to confirm some basics on the fitting of HF wire antennas on aircraft. Please refer to the following URL: http://jproc.ca/test/avenger%20_antennas_v1.JPG Questions: 1) With respect to the 'T' joint which I have circled in both diagrams, is that just a bonding point where the vertical feeder meeds the horizontal section? I'm assuming that the feed line is just a solid wire and not coaxial cable. 2) Assuming the answer to question 1 is a bonding point, can I assume that a HF antenna in this configuration is just a T shaped radiator that uses the aircraft's skin as the counterpoise? 3) May I safely assume that an aircraft anntenna is an inefficient radiator of RF since this aircraft itself is too short to support a length of wire which is resonant anywhere in the 3 to 6 or even the 6 to 9 MHz bands?. 4) Does it matter where the feedline attaches to the horizintal wire? . ie Does it make much difference if the antenna is a symmetricalal 'T' verus an aasymmetricalal 'T'? The problem here is the labelling of the bottom diagram. It implies that half the antenna is used by the ARB receiver and the other half by the ART 13 transmitter. This is wrong and the labelling should simply say "HF antenna" since the transmitter and receiver would take turns using it. -- Regards, Jerry Proc E-mail: jerry7proc@yahoo.com __________________________________________________________________ Looking for the perfect gift? Give the gift of Flickr! http://www.flickr.com/gift/ ------------------------------ From: wb3fau@att.net To: Old Tube Radios Cc: Daniel Wright Subject: Re: RME 4350 Help! Date: Sun, 31 May 2009 18:35:23 +0000 Message-Id: <053120091835.1080.4A22CDEB0009D9A10000043822243322829B0A02D29B9B0EBF9A0E00CC0D99@att.net> I take it that the 4350 is deaf on all bands? Do you have some test gear? How about a quick check of the IF stages? You have the manual, follow the proceedure given. RF alignment may also need done. If all the tubes are good, alignment does not help, something in the front end may be fried. It could have taken a lightening hit. These are usually pretty sensitive receivers. Russ. ------------------------------ Message-ID: <4A22D2F9.9060500@aafradio.org> Date: Sun, 31 May 2009 14:56:57 -0400 From: AAFRadio MIME-Version: 1.0 To: Old Tube Radios CC: Old Tube Radios Subject: Re: HF Aircraft Antennas Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Jerry Proc wrote: > Please refer to the following URL: > http://jproc.ca/test/avenger%20_antennas_v1.JPG > > Questions: > > 1) With respect to the 'T' joint which I have circled in both diagrams, is that just a bonding point where the vertical feeder meeds the horizontal section? That's correct. > I'm assuming that the feed line is just a solid wire and not coaxial cable. > Again correct. > 2) Assuming the answer to question 1 is a bonding point, can I assume that a HF antenna in this configuration is just a T shaped radiator that uses the aircraft's skin as the counterpoise? > There's been quite a bit of debate on this issue, the gist of which suggests that the vertical feedline provides the majority of effective radiation, with the wire parallel to the fuselage providing the equivalent of a capacity hat. I think the jury's still out on it...the engineers certainly had a different view back in the war. I've always thought it was one of those debates that has no real conclusion except for each specific case, since the geometry was a bit different for every aircraft. > 3) May I safely assume that an aircraft anntenna is an inefficient radiator of RF since this aircraft itself is too short to support a length of wire which is resonant anywhere in the 3 to 6 or even the 6 to 9 MHz bands? > Yup. With radiation resistance typically below 10 ohms, you also get heating losses due to the high currents in the antenna and ground screen (fuselage). It's one reason they liked to carry a trailing wire antenna on the larger aircraft...the vertical droop of a trailing wire hung out some distance provided a more effective radiation pattern for HF work. > 4) Does it matter where the feedline attaches to the horizintal wire? ie Does it make much difference if the antenna is a symmetricalal 'T' verus an aasymmetricalal 'T'? > Nope, at least as far as the radiation resistance is concerned. See http://aafradio.org/docs/Aircraft_Antenna_Design.html and you'll find they don't make any allowances for the feed point, other than to differentiate between feeder and antenna sections for length calculations. They do show most of the variations to make sure you know which is which. > The problem here is the labelling of the bottom diagram. It implies that half the antenna is used by the ARB receiver and the other half by the ART 13 transmitter. This is wrong and the labelling should simply say "HF antenna" since the transmitter and receiver would take turns using it. > Yup, you have it right. 73, Mike KC4TOS ------------------------------ Message-ID: <52435BC9A93E4DC9B2BD67EEECEA6FD7@userd0315415c7> From: "Michael Hardie" To: Old Tube Radios Subject: Two Questions Date: Sun, 31 May 2009 13:21:58 -0700 MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original Content-Transfer-Encoding: 7bit 1. I've had two transmitters that have regulated B+ on the VFO screens (DX-100 and Ranger) but the B+ on the plate is unregulated. Why is it more important to have the screen voltage regulated? 2. Older RF chokes don't seem to have ferrite or powdered iron cores, most of the newer ones do. What problems can occur when using the ferrite/iron core type in a circuit that used to have a "non core" choke? Mike VE7MMH ------------------------------ From: Gary Woods To: Old Tube Radios Subject: Re: Two Questions Date: Sun, 31 May 2009 16:26:49 -0400 Message-ID: <1rp525dou80hpavp835gp7mo4j1rcrlutl@4ax.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit On Sun, 31 May 2009 13:21:58 -0700, you wrote: >1. I've had two transmitters that have regulated B+ on the VFO screens >(DX-100 and Ranger) but the B+ on the plate is unregulated. Why is it more >important to have the screen voltage regulated? The VFO is likely an "electron coupled" circuit: The oscillator portion uses the screen as the anode (grounded for RF; feedback via the cathode), and the plate is almost like a buffer stage, so voltage regulation not so important. I'll defer on the choke thing, other than to guess that ferrite cores are more easily saturated, though making for a smaller package with less wire. Gary Woods AKA K2AHC- PGP key on request, or at home.earthlink.net/~garygarlic Zone 5/6 in upstate New York, 1420' elevation. NY WO G ------------------------------ Mime-Version: 1.0 Message-Id: Date: Sun, 31 May 2009 14:25:42 -0700 To: Old Tube Radios From: Scott Robinson Subject: Re: Two Questions Content-Type: text/plain; charset="us-ascii" ; format="flowed" Hi Mike, 1) A pentode doesn't much care what it's plate voltage is--except for dissipation and max voltage issues--so long as the screen is held steady. That's why only the screen is regulated. 2) The ferrite or powdered iron core choke will likely have a higher Q, which you can fix with parallel resistance if peculiar oscillations show up. Regards, Scott >1. I've had two transmitters that have regulated B+ on the VFO >screens (DX-100 and Ranger) but the B+ on the plate is unregulated. >Why is it more important to have the screen voltage regulated? > >2. Older RF chokes don't seem to have ferrite or powdered iron >cores, most of the newer ones do. What problems can occur when >using the ferrite/iron core type in a circuit that used to have a >"non core" choke? > >Mike VE7MMH ------------------------------ Message-ID: <003a01c9e24b$89060ef0$b89f480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: HF Aircraft Antennas Date: Sun, 31 May 2009 16:38:22 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit > ......There's been quite a bit of debate on this issue, ....... This comment reminds me of the old bugaboo I had to overcome that anything that is not turned into heat gets **radiated.** Of course, debating is what sustains ignorance. Study answers questions. The two problems needing solving are how to build an antenna system that doesn't convert two much RF into heat and which direction do you want the RF to go. You don't have too many choices on which direction the RF will go at HF. The question I would like an answer to is how are HF antennas incorporated into modern aircraft as there are no more external wires to be seen (or is it my weak eyes...???)? Arden Allen KB6NAX Adopt a shelter dog, save an innocent life, and make a friend forever =:-) ------------------------------ Message-ID: <003b01c9e24b$8a6e9fa0$b89f480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Subject: Re: Two Questions Date: Sun, 31 May 2009 16:56:27 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit > ...Why is it more important to have the screen voltage regulated? By stabilizing the screen voltage you are stabilzing the transconductance over a wide range of plate (and screeb) currents which make the tube more efficient to drive. > ...What problems can occur when using the ferrite/iron core type in a circuit that used to have a "non core" choke? As was pointed out you can saturate the ferrite or iron core with enough current. The distortion caused generates harmonics, not what you want a tuned circuit to do necessarily. Also, if the temperature coefficient of a core is not reasonably matched in opposition to the temperature characteristic of the coil the resonant frequency will change with temperature. And lastly, the increased efficiency, i.e., increased Q over an air core coil can make amplifier stability (freedom from oscillation) tougher to deal with. There are myriads of ferrite/iron coil tuned circuits in existence loaded with resistors to bring their Q's down to more manageable values. Arden Allen KB6NAX Adopt a shelter dog, save an innocent life, and make a friend forever =:-) ------------------------------ Message-ID: <000d01c9e24c$8fcc90f0$b89f480c@KB6NAX> From: "Arden Allen" To: Old Tube Radios Cc: "Old Tube Radios" Subject: Re: HF Aircraft Antennas Date: Sun, 31 May 2009 17:04:17 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Regarding http://aafradio.org/docs/Aircraft_Antenna_Design.html I guess the author was a Douglas man and the illustrator was a Lockheed man. ;-) Arden Allen KB6NAX Adopt a shelter dog, save an innocent life, and make a friend forever =:-) ------------------------------ Message-ID: <4A2324D0.2030707@pacbell.net> Date: Sun, 31 May 2009 19:46:08 -0500 From: Dan Arney MIME-Version: 1.0 To: Old Tube Radios CC: Old Tube Radios Subject: Re: HF Aircraft Antennas Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Arden, most of the early jets in international serevice used probe type anyennas at the top of the vertical on the B-707-300C and earlier B-747 DC-8's used a flat panel section of the vertical fin some use the wing tip. Nearly asll of the current aircraft use flat panels in all cases for all services including navigation, RADAR altimter, ground proximity All of the HF use a fast antenna tuner. The new ones in less than 3 seconds Hannk ------------------------------ End of BOATANCHORS Digest 4271 ******************************