Which brings me to my question: One of the ganged tuning cap's wire coming from its top is disconnected. The other one goes to the 6A8 cap terminal, which is its grid #4. I looked at the schematic, and the tuning cap is supposed to be C1. I see the two C1's in the schematic. One does show connection to grid 4 as observed. The other shows it going to the net between C4 and the shortwave oscillator trimmer cap (K) in parallel with the antenna coil & shield assy (S-5073).

Does anyone know exactly where this would have normally tied in, since it is not apparent to me. My plan is to feed it back down through the chassis, and connect to C4/R1 net, or is there a better way? The original wire is only 2 inches long at most and looks like it had a terminal connected to it at one time that snapped. Are the posts on top of the coils of any use electrically? I'd rather not dissect the entire coil by disconnecting it all and taking it apart, but I am trying to 'keep it original' as possible. I am sure someone here knows off the top of their head!

Thanks in advance,
Dave

6/29/2009 3:59:29 PMDave A.(75430:75417)

Dear Sir de Edd, most extinguished member of the forum, it is a pleasure to be the recipient of your detailed response. Thanks :-)

I am aware of the location of the S-5073 coil, and there are two terminals on top (posts with nuts). Please define "stator", as this brings to mind a motor. I am thinking of this as a coil/choke/transformer that consists of a set of windings and a core (though it may be air). This is where it appears the ORIGINAL (yes, cloth coated ala 1930s) wire was connected.

If it cannot be connected there, these tuning condensers are right next to the coils on the top of the chasis, and I would have to replace and run that wire down through a hole in the coil or chassis to get to my known location of the net that the schematic is showing. Adding a ring terminal and screwing/unscrewing a nut would be MUCH easier - no soldering, and (maybe) original :~).

Just for this occasion, I have created a free hosting account. If this photo shows up, I will post the real one later when I have access to it:

The Me-hican station sounded VERY authentic, with a VERY fast-speaking announcer - yet I am in Ohio...where there does reside a sizeable el chicano population.

Warning, extreme old radio newbie comment - I will attempt to read the Black and Red needles to determine the reported station frequency location (where's the LCD?...).

...to be continued...

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Sir Dave. . . .A. . . . I can think of a couple of possibilities to confirm. First, congrats on bringing life back into the ~70 year old unit, and even more impressive is where you done it. Now, we have BCBand, Police Band, Longwave, Midwave, Shortwave and Groundwave. . .but. .but...BUT...BUT...BUT "You'se got's BASEMENT wave ! " And assumedly, it being from a local Mejicano station, or possibly you are near the Cal-Nev-Ariz-NM-Tex border and reaching across to get a REAL Mexican station . Seems like I usually find mine being at either extreme of the band with the most of them being near the 540 end. I don't have a 5664 chassis at hand to electro-mechanically reference , but a schematic positional referencing revealed the two sections of the dual C1 tuning condenser sections having its top left unit being the RF section and having the bottom right cornerwise one being the Oscillator section. Expecting the unit being mounted 90 off from the chassis plane. That could then have the placement of two terminals placed at the top of the tuning condenser for the stator sections with TWO more stator terminals duped and ALSO being available at its very BOTTOM side, next to the chassis. Wiring connection could be made there and routed thru a hole(s) in the chassis to connect to circuitry. Very likely, that is what has been done on the oscillator section. Your other top tuning condenser wiring is for the RF section where it assuredly is having that RF stator being connected to the osc grid circuitry of the 6A8, for you to now be getting any reception at all. As for the tuning condensers connection to osc grid capacitor C4 , I believe that connection is being made thru a hole in the chassis to the bottom stator connection of the tuning condenser osc section. Reviewing the number of connections that are shown on the RF section. . . 1... The electro-mechanically built in trimmer capacitor K 2...A wire over to the shared junction of the top of the RF coil and its companion trimmer L 3...A wire to the RF grid of the 6A8 tube Reviewing the number of connections that are shown on the OSC section. . . . 1... A wire over to the junction of the top of the oscillator coil and its companion trimmer capacitor K. 2...A wire over to grid coupling capacitor C4. . .probably located as mentioned above. I never could confirm what your loose ended wire was connected to, the stator or the RF or OSC section, or possibly the frame of the tuning condenser ? Also, if it seemed to be ORIGINAL wiring. If added on later, I know as a fact . . .as a 10 year old. . . .that in experimenting with a short length of hook up wire being used for an antenna, if I hooked it up to that antenna connector and let the RF get coupled in thru that link winding into the antenna coil, I would get a certain level of performance, BUT that if I then moved that wire connections position over to the tuning condenser RF stator, my stations reception was a bit stronger. Should I have had been using a much longer antenna wire, the input into the designated Ant connector would have matched appropriately, with the performance equating on a same level. One other question might be as to what the frequency of the received station is and if it does seem be coming in somewhat near that logging on the dialscale ? Also try this, get the received station tuned in ....spot on. . . and then start a progressive tensioned grasping of the the osc stator connection, using thumb and index finger and see if that shifts off the tuning to the station. If not, there just might be an oscillator presence problem. Standing by. . . . 73's de Edd

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: : : : : : : : : : : : : : : :Sir Dave. . . .A. . . . : : : : :I can think of a couple of possibilities to confirm. : :First, congrats on bringing life back into the ~70 year old unit, and even more impressive is where you done it. 6/29/2009 7:35:12 PMDave A.(75437:75430) Let's try this again. The bottom tuning cap wire (lower middle of pic) is the one in question. It is wrapped around the other ganged tuner cap. The coil is the one on the upper right that it must connect to. 6/29/2009 7:42:13 PMDave A(75438:75437) I try again...one of these ought to work... F2 [url=http://img132.imageshack.us/my.php?image=1003392c.jpg][img=http://img132.imageshack.us/img132/4791/1003392c.th.jpg][/url] F1 [URL=http://img132.imageshack.us/my.php?image=1003392c.jpg][IMG]http://img132.imageshack.us/img132/4791/1003392c.th.jpg[/IMG][/URL] W S 6/29/2009 10:12:28 PMEdd(75443:75438) Sir Dave. . . .A I also might have to break off and make this a continuance, but first I’m upping the photo sizing from its supplied thumbnail size And placing it down at the bottom. Seems like the extra wire you have found is a planned situation, during the final test and alignment of the unit at the factory. BEHOLD. . . the “gimmick “ capacitor. Seems like they were finding that the degree of oscillator injection into the mixer stage was a little less that optimal on the very highest frequencies, thereby the upping the level of oscillator signal into the 6A8 tube, in excess of the distributed interelectrode capacitance betwixt the tube elements, by that gimmick capacitor. The situation being a variable unknown, thus not using a fixed low picofarad value of capacitor. The gimmick can be a variable value capacitor in its manner of selecting the number of turns encircling the second wire, along with the tightness of the wrap. One wire being “one plate” of the capacitor, the other wire being the “other plate” with the insulation / spacing being the variable dielectric factor. They were merely adjusting that factor until the receiver JUST operated reliably across the band on the highest frequencies. The second query was in the order of the dual section tuning condenser, the movable vanes are name assigned, the “rotors” designation, whilst the fixed plates mounted way down within the unit are called the “stators”. With your photo, the RF sections routing over to the input grid cap of the 6A8 is readily apparent now, so with the front section being the oscillator, you should now be able to go down to the base of the 6A8 and locate its osc grid resistor R1 and that all important grid coupling capacitor C4 and track down its outer end to see how it gets connected/ routed to its connection to the oscillator stator of the tuning condenser. A quick confirmation. . .jab one ohmmeter probe onto the outer C4 connection, the other probe to the stator connection of the osc connection. . . .Zero ohms ? 73's de Edd Zee-Nuts Photo. . .on steroids : 6/29/2009 10:37:16 PMDave A(75445:75443) Thanks once again, Edd!! Hmmm, the 'gimmick cap' - not very scientific, yet an effective solution...this is very interesting. That makes sense now, based on my latest findings. Sorry about the thumbnail - I tried full size first. With a little more HTML hacking, I am sure I will get it just right. I guess the thumb is lower bandwidth, and loads 0.00047 secs faster for those who aren't as interested ;~) Best Regards, Dave 6/30/2009 7:18:32 AMEdd(75456:75445) 6/30/2009 12:56:56 PMDave A(75461:75456) Señor Edd - Valuable advice...and I think I solved the station mystery. Yes, I meant 1600kHz, it was 1617.5 to be exact. BUT, the local Spanish station is actually located at 1550kHz, reinforcing the need for alignment. According to http://www.radio-locator.com/ they also have a daytime power of 500W and a nighttime power of 39W. When I could not receive it anymore, it was nighttime. Still interesting that was the only station I got, but what can I expect with a short hookup wire antenna in the basement (base-wave, eh?). Thanks for the alignment reference. I will review it. Dave 6/29/2009 10:27:20 PMDave A(75444:75417) Well, I may be talking to myself here, but anyway...I ohm'ed out (yea, Ohm's Law still works, Dave) the connection to C4 and it ALREADY goes to C1...hmmm, both connections seem to be original wiring, which leaves me scratching my head. Also, the ground straps are both securely wired. Even more interesting, the estación de radio Mexicana is gone that the set previously reported at about 160 kHz. This is beginning to remind me of Steven Speilberg's Christine...But yesterday was a very clear day and today is somewhat cloudy. Either way, when I get more time I need to bring it up from the basement and put on a proper antenna to try again. Regarding alignment, can a standard signal generator with modulation be used? What signal amplitude should be used? I suppose there is also the idea of just using another calibrated radio for comparison, but when starting at ground zero, it seems that a signal generator would be preferred. Remember, be kind since this is my first restoration, and soon to be my first alignment. The oldest things they taught me in school were FORTRAN, the Z80 microprocessor, and drafting with a pencil instead of a computer. At least Ohm, Kirchoff, and Norton's rules never change... :Dave 6/30/2009 1:29:23 PMLewis L(75462:75444) :Well, I may be talking to myself here, but anyway...I ohm'ed out (yea, Ohm's Law still works, Dave) the connection to C4 and it ALREADY goes to C1...hmmm, both connections seem to be original wiring, which leaves me scratching my head. Also, the ground straps are both securely wired. : :Even more interesting, the estación de radio Mexicana is gone that the set previously reported at about 160 kHz. This is beginning to remind me of Steven Speilberg's Christine...But yesterday was a very clear day and today is somewhat cloudy. Either way, when I get more time I need to bring it up from the basement and put on a proper antenna to try again. : :Regarding alignment, can a standard signal generator with modulation be used? What signal amplitude should be used? I suppose there is also the idea of just using another calibrated radio for comparison, but when starting at ground zero, it seems that a signal generator would be preferred. : :Remember, be kind since this is my first restoration, and soon to be my first alignment. The oldest things they taught me in school were FORTRAN, the Z80 microprocessor, and drafting with a pencil instead of a computer. At least Ohm, Kirchoff, and Norton's rules never change... : ::Dave Dave: When we started with computers at Delta, we went to computer school, naturally. We 8080, Z80 680 we also learned learned Octal, Hexadecimal, and of course, Binary. One joke was: I can prove Christmas comes on Halloween. You see, Decimal 25 is Octal 31, so Dec 25 equals Oct 31. Nobody in todays bunch of computer whizzes can understand that. They don't know enough of the basic stuff to catch it. Ah, memories Fortran Cobal C C+ and on and on......... Lewis 6/30/2009 1:31:43 PMLewis L(75463:75462) ::Well, I may be talking to myself here, but anyway...I ohm'ed out (yea, Ohm's Law still works, Dave) the connection to C4 and it ALREADY goes to C1...hmmm, both connections seem to be original wiring, which leaves me scratching my head. Also, the ground straps are both securely wired. :: ::Even more interesting, the estación de radio Mexicana is gone that the set previously reported at about 160 kHz. This is beginning to remind me of Steven Speilberg's Christine...But yesterday was a very clear day and today is somewhat cloudy. Either way, when I get more time I need to bring it up from the basement and put on a proper antenna to try again. :: ::Regarding alignment, can a standard signal generator with modulation be used? What signal amplitude should be used? I suppose there is also the idea of just using another calibrated radio for comparison, but when starting at ground zero, it seems that a signal generator would be preferred. :: ::Remember, be kind since this is my first restoration, and soon to be my first alignment. The oldest things they taught me in school were FORTRAN, the Z80 microprocessor, and drafting with a pencil instead of a computer. At least Ohm, Kirchoff, and Norton's rules never change... :: :::Dave : : :Dave: :When we started with computers at Delta, we went to computer school, naturally. We 8080, Z80 680 we also learned learned Octal, Hexadecimal, and of course, Binary. One joke was: I can prove Christmas comes on Halloween. You see, Decimal 25 is Octal 31, so Dec 25 equals Oct 31. Nobody in todays bunch of computer whizzes can understand that. They don't know enough of the basic stuff to catch it. Ah, memories Fortran Cobal C C+ and on and on......... :Lewis P. S. 680 above shud be Motorola 6800. Also, still having trouble getting this forum to work. Lewis 6/30/2009 9:22:49 PMDave A.(75476:75463) Lewis, At my place of business, we recently discontinued our last product that used the 6809 about 5 yrs ago. We are still using the HC11 and latest incarnation of the 68k core in the new ColdFire family. Our main focus for projects in college was on the 8051, which is amazingly still being proliferated today. Another joke is: There are 10 types of people in this world - those who understand binary and those who don't :-) Well, better get back on topic or mr. anonymous will get all frazzled again. Yes, I've had to enter the Forum via the search page. for at least a week now - not sure what the cause of the re-direct issue is or if it will be fixed. D :: :: ::Dave: ::When we started with computers at Delta, we went to computer school, naturally. We 8080, Z80 680 we also learned learned Octal, Hexadecimal, and of course, Binary. One joke was: I can prove Christmas comes on Halloween. You see, Decimal 25 is Octal 31, so Dec 25 equals Oct 31. Nobody in todays bunch of computer whizzes can understand that. They don't know enough of the basic stuff to catch it. Ah, memories Fortran Cobal C C+ and on and on......... ::Lewis : :P. S. 680 above shud be Motorola 6800. Also, still having trouble getting this forum to work. :Lewis © 1989-2025, Nostalgia Air Sir DAVE. . . .A Well, I may be talking to myself here, but anyway...I ohm'ed out (yea, Ohm's Law still works, Dave) the connection to C4 and it ALREADY goes to C1...hmmm, both connections seem to be original wiring, which leaves me scratching my head. Also, the ground straps are both securely wired. THAT confirms it then, and certainly you can NOW find the connective means ? Even more interesting, the estación de radio Mexicana is gone that the set previously reported at about 160 kHz. This is beginning to remind me of Steven Speilberg's Christine...But yesterday was a very clear day and today is somewhat cloudy. Either way, when I get more time I need to bring it up from the basement and put on a proper antenna to try again. I hope you mean 1600 Khz. . . . so does that mean no stations now received at all. . . . so that you could confirm the "skewing " of the osc frequency to a "de-tuned" off station condition by the grasping of its exposed stator terminal ? Regarding alignment, can a standard signal generator with modulation be used? What signal amplitude should be used? I suppose there is also the idea of just using another calibrated radio for comparison, but when starting at ground zero, it seems that a signal generator would be preferred. Use a standard signal generator with its audio tone modulation turned on, and using enough RF level to initially "find" the signal and then backing down on the RF level to the point where only the least level required, to just be heard, is present. A good superhet alignment "how to do-it-to-it" tutorial can be found at : http://www.antiqueradios.com/archives/ElementsOfRadioServicingCh21-24.pdf Of which , you are interested in chapter 22 of that cluster of chapters. Remember, be kind since this is my first restoration, and soon to be my first alignment. The oldest things they taught me in school were FORTRAN, the Z80 microprocessor, and drafting with a pencil instead of a computer. At least Ohm, Kirchoff, and Norton's rules never change... Zee-80. . . .ZEE-80. . . .How's about , just post ENIAC days, with its 5600 12AU7's and moving on into the first utilization of discrete transistor circuitry. Therein, utilizing MASSIVE counts of 2N404's paired and wired as F/F's. And then, the black magic miracle. . . . memory / storage/ access via hand "laced" micro ferrite bead, memory core planes. Pee Ess : I am seeing no viable alternative in incorporating the MOC 3011 into the plan, other than the concurrent utilization of a companion Triac in order to make an ultra reliable power switch circuit. 73's de Edd