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B-24A Radio Rack Restoration http://warbirdinformationexchange.org/phpBB3/viewtopic.php?f=26&t=26433	Page 3 of 4

Author:	Django [ Wed Dec 17, 2008 5:14 pm ]
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Gary, FWIW, your passion for the old girl is what prompted me to get involved with the project in the first place.

Author:	Second Air Force [ Wed Dec 17, 2008 5:20 pm ]
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Django wrote: Gary, FWIW, your passion for the old girl is what prompted me to get involved with the project in the first place. Ellen and I second that sentiment, and we were pretty darned proud of what you accomplished, Gary. Scott

Author:	CAPFlyer [ Wed Dec 17, 2008 6:55 pm ]
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Gary, actually, I was looking at the apparent height between the windows and the top of the desk which made me think either it was a short desk (if the current floor is at the right height) or during the modifications post-bomber, the structure was raised in that area and thus you were unable to lower it back to the original height. Not claiming you were doing anything wrong, just working with what you had. BTW, I am taking measurements tonight at the meeting for the exact reason you state Gary - I need to find out how tall that table really is so I can get and cut the metal to the right height. Thankfully, I've got a trial version of AutoCAD which should help me immensely in designing the new table as it'll let me work out things in a 3D environment so that I can try to get this thing right the first time.

Author:	CAPFlyer [ Wed Dec 17, 2008 11:36 pm ]
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Okay, now at work after an excellent meeting (CAF Prez. Steve Brown was even present as he happened to be in town for an unrelated meeting today). Work party tomorrow (Thursday) from 3:30pm to 7:30pm for anyone in the area that wants to get dirty. I've got to do inventory on the spares for Dave tomorrow (there will finally be someone there with a key to the spares room), but there will be others working on finishing dismounting the #3 we borrowed from Cavanaugh so they can get it out for overhaul as it was supposed to do before we borrowed it (thanks again Doug!). On the front of the B-24A radios - I measured the compartment to make the AutoCAD model. Thank goodness for consistently sized and constructed spaces. The arc will be interesting to get right, but beyond that, the stucture is very simple and should be easy to replicate so I can get an accurate plan made for the table. Once I get that complete, I will be contacting both the NASM & NMUSAF to see if they have additional photographs of the radio setup in the B-24A or any diagrams or manual excerpts before I finalize the design. It will be a simple tube aluminium and wood desk with very few refinements (as in the picture). The radios will all be dummy units. I have found that the BC-450 has nowhere to mount as the mounting location for the unit is a canvas cover instead of a solid wall. The BC-378 will be gutted or another unit gutted and a modern AM(/FM) radio installed. The controls will be modified to control this radio in addition to modifying the current switches to control the radio and 2 associated items. The first associated item will be an "Aux" channel that will be a CD player, MP3 player, or Satellite Radio receiver for the purpose of playing period appropriate music. The second associated item will be overhead speakers in the rear of the aircraft (out of the way of any potential future modifications) that will allow for us to play the period appropriate music while on the ground at airshows. The switch controlling the speakers will switch between headset and speakers allowing for anyone sitting near the radio to listen to the radio inflight on headset(s). The remaining units will be mocked up units with faceplates and light aluminium covers to look correct but be as light as possible. I would like to thank Robbie for his help in this matter so far and future help. It is really nice to have the kinds of resources that we have on here to be able to make these projects possible to not only have something that looks correct for the airplane but is a neat functional item that will not just take up space but benefit our presentation of the aircraft to the public.

Author:	K5DH [ Fri Dec 19, 2008 8:29 pm ]
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Radio dude here. . . I just discovered this thread. I've been sick all week, including a fun visit to the ER on Wednesday (thankfully it was nothing serious, as it turns out). CAPFlyer: Even talking about gutting out that BC-348 is like stabbing a big ol' serrated survival knife right into my heart! I understand why it's being done, but that doesn't mean I have to like it. BTW, your '348 has been "ham-ified". They did not run on 115 VAC. As Robbie correctly pointed out, it was commonplace after BC-348s were surplused for hams to buy them (staggeringly cheap!) and modify them to run on house power. That meant removing the 28 VDC dynamotor power converter, building and installing a homebrew AC-operated power supply, and usually rewiring the tube filament string to run on some more common voltage like 6.3 VAC (which was easy; you just put all eight filaments in parallel since they were all 6.3 Volt tubes!). Other mods were common, too, including mods to the audio output stage. As you can see with your set, hams back then had little regard for the restorers of the future, and they carelessly drilled holes in the front panels and cabinets, hacked up wiring, and so on. I have one like that which I'm in the process of fixing up (not restoring... too far gone for that!). But, I digress. . . If you come up with a complete, correct list of the original radio gear that was used in the B-24A, please send it to me. I have a number of contacts through which I've obtained original radio items for VFM. I'll do some snooping around for you. Between Robbie and me and a few other WIXers, we can at least get you started. One last comment. The BC-348-J is much too new for a pre-war aircraft. the -J came out in 1943, I believe. Once in a great while, I'll see one of the early models for sale, but they're rare and pricey. 73! (in "ham-speak", that means "Best Regards")

Author:	Robbie Roberts [ Fri Dec 19, 2008 9:09 pm ]
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Dean- The -J designator pretty much was just an indicator of maker, rather than of date... But I had a different question: Which would be more correct for a pre-war B-24- a BC-348 or a BC-312? Robbie

Author:	CAPFlyer [ Sat Dec 20, 2008 12:02 am ]
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Oddly enough, I've found pictures of dual BC-348s being installed on AM927 in the past during her life with Continental Can. They look to have been installed "up front" facing aft, although with our reconfiguration of the airplane since rescuing it, I can't be 100% sure simply because I've not seen the plane before Gary got to it and did all his beautiful work. On the radio front - We looked at the topside of the airplane last night. We discovered that the tab for the Command Radio HF wire is still installed on the left stabilizer. As such, we have all of the hardware in place to wire up that antenna. We will be installing the antenna in the coming weeks and dropping a line into the aft fuselage through a pre-existing access (still have to figure out where that will be) to hook up to the radios. Should be fairly straightforward as all of the required hardware is installed and I've been informed that we may have a source for the required wire, connectors, isolators, & tensioning springs to be donated to us for the project. I have a question as I've not seen much of the photos that Gary has so maybe Gary can answer it - did AM927 have 2 HF antenna like the D models? I don't have any plans to try and install a second wire if it did exist, but we didn't even think to look and see if there was any evidence.

Author:	K5DH [ Sat Dec 20, 2008 11:08 am ]
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Robbie Roberts wrote: Dean- The -J designator pretty much was just an indicator of maker, rather than of date. Yes, that's true. However, the contract for the -J was issued to Wells-Gardner in 1942 (I was off by one year). The BC-348 was a 28 VDC version of the BC-224, which ran on 14 VDC. Apparently, in the 1930s, Army aircraft commonly used 14 VDC radios. The BC-348-B contract was issued in 1939, and the -C contract was issued in 1941. The designators BC-348-A, -D, -F, -G, and -I were never used. The -E was a modification to add 200 - 500 kc coverage to the earlier -B and -C models. BTW, I own one each BC-348-H, -J, -Q, and -R. The -J and -Q are stock, original, working units with dynamotors installed. The -R is also stock, but missing its dynamotor, and I've never powered it up. The -H was terribly mistreated by previous owners. I intended it to be a parts unit, but I decided that, although it could never be restored to stock condition, it wasn't too far gone to at least make it operational for hamming. So, I'm working on that. Here's a photo of my BC-348-J: Robbie Roberts wrote: .. But I had a different question: Which would be more correct for a pre-war B-24- a BC-348 or a BC-312? That's why I'd like to see the actual USAAC radio equipment specs for the B-24A. I'm not sure that any BC-348 model is correct. 73, Dean K5DH

Author:	Robbie Roberts [ Sat Dec 20, 2008 11:35 am ]
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Hi Dean- I know exactly what you mean about modded 348s... I have two- My late Uncle Bill's, BC-348 Q which I converted back to 24VDC, but built a purpose specific transformer for, since I did not have a dynamotor, and a second one, a BC-348P, which I have been converting back for a while now, when I get the chance. I was actually lucky enough to trade for an original mount & dynamotor for that one! (It will be part of the traveling radio display & fully operational). I am still troubleshooting a bad hum with the 348P. The 348Q is part of my ham shack equipment now.(Although I can always throw the dynamotor in when I wish to. If you can get me the SCR numbers for the spec radio equipment, I should be able to tell you exactly what should be in there. If the BC-312 is involved, I have a spare parts unit I can build into a dummy unit instead of the 348. 73! Robbie KC2TYV

Author:	retroaviation [ Sat Dec 20, 2008 12:44 pm ]
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k5dh wrote: That's why I'd like to see the actual USAAC radio equipment specs for the B-24A. I'm not sure that any BC-348 model is correct. 73, Dean K5DH Well, the pictures below will likely be of little use to y'all, since they're listing the RAF radio packages, rather than the USAAC, but nonetheless, I thought you "Ham-heads" would like seeing them. These are pages from the original paperwork on Ol'927, prior to it's acceptance by the British. I tried to only include the radio stuff so that I didn't bore you with page after page of instruments, armament, etc..... Gary

Author:	Alan Brooks [ Sat Dec 20, 2008 1:55 pm ]
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Gary, you just made the day for Robbie and Chris! HUUUUUMMMMMM Alan

Author:	Django [ Sat Dec 20, 2008 2:58 pm ]
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It had carpet?

Author:	retroaviation [ Sat Dec 20, 2008 4:11 pm ]
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Django wrote: It had carpet? Yup, and those nice interior panels that you saw in the first picture I posted. I would imagine that those were the first things to come out once the maintenance crew got a hold of it. Gary

Author:	K5DH [ Sat Dec 20, 2008 4:14 pm ]
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Gary: Great info! All of the radio gear listed is US issue. CAPFlyer: Looks like Ol '924 had a BC-348-B and BC-375-C in the Liason position. That's going to be a very difficult set of gear to find, especially since there was a tech order issued to upgrade the -B and -C models to add the 200 - 500 kc band. I've never seen a BC-375-C, but the -E model is fairly common. I don't believe there was a -D. On the plus side, most of the public would not know the difference if newer models were substituted. If some nit-picker calls the bluff, just tell them that those are merely "representative placeholders" until the correct ones can be found, and then ask them if they have any correct ones they'd like to donate! The mounting bases, tuning units, and other accessories will be the same as those used with the later sets, so you should be able to find all of that. I'll have to look closer at Gary's info. There are a number of items listed that I'm not familiar with, but I probably should get that way. Robbie: I guess Gary's info answers the question about which Liason receiver belongs aboard the airplane. (And, I was right after all! ) 73, Dean K5DH

Author:	CAPFlyer [ Sat Dec 20, 2008 5:15 pm ]
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Well, as we're going to "nameplate" most of the stuff, I think we can get at least part of it right. What I really need are more pictures of the radio compartment and the where everything was located on each rack and what was on and under the table. From that I can figure out what's really possible to put in.

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