22 responses

  1. Lou
    June 9, 2012

    Now working on my 6th SX 28, 28A restoration…I always remove the RF sections..I have developed a procedures whereby I can now remove the four RF sections in about a couple of hours..Removing the sections gives you much better access to the IF,power and audio areas..In the SX 28 Iam now restoring I found that the primary windings on the antenna coils for bands 1 and 2 are open..So that’s going to be a challenge to repair…

    Lou..

    • Thomas
      June 9, 2012

      Wow, your 6th. Great that you’ve got the techniques down, as it can really reduce the time consumed. Removing the RF sections would certainly give you more room to work. I considered it but found that I was able to develop new techniques that allowed me to replace all the caps and resistors without removal. If I was retired and had the time, I’d probably do it your way. Good luck rewinding the antenna coils. I wonder what made them open up.

      • Lou
        June 17, 2012

        Don’t know what caused the open primaries..There is no evidence of burning…Probably have to get an SX 28 as a spare parts radio..The coil wire is very thin and can’t be handled very well….

      • Lou
        July 11, 2012

        Just picked up a couple of SX 28A’s..The A model is much easier to work on..The RF section has individual modules that have the tube socket as an integral part of the module…Of course you still have to unsolder all the wiring to the main and bandspread caps…

      • Chuck K7MCG
        May 15, 2013

        Lou-
        I have just acquired an SX-28 that sadly was stripped of all its knobs, except the AGC/BFO knob, by a previous owner. Do you have any knobs for sale from your parts hulks ? I also need the logging scale and dial lock.
        Thanks & 73
        Chuck K7MCG

      • Thomas
        May 16, 2013

        You can contact me at tom AT cpic.net. I do have a set of knobs.

    • Steve Larrabee
      December 18, 2012

      Hi: 12/18/12 — I am working on a SX-28 (not the 28-A model) and the Band 1 antenna coil in the RF section (1st coil in Band 1) it is T-13 — has the bottom coil burned/cooked. Sounds like you have faced that repair in yours. Would you by any chance know the inductance of that bottom coil on T-3? The top two windings are 180 uhy on my T-3.
      Thanks very much.
      best, Steve

      • Thomas
        December 19, 2012

        Hi Steve,

        I did not face any problems with T-3. Sounds like your set either took a minor lightning strike OR, more likely, someone managed to transmit into the receiver due to some problem with their switching relay. I looked in the military version of the SX-28 manual, and all it says for T-3 is that it is a 455KC IF coil. You could probably calculate the correct value, at least ballpark, by determining the “effective impedance” that this coil connects to. The coil would be aligned to minimum impedance at the 455KC IF frequency, giving you maximum signal transfer. What makes this more complicated (and the reason I said “ballpark”) is that this is not an air core inductor. The impedance is instead varied by the slug and there is really no way to predict things without experimentation. You could calculate the correct IF value, then remove the coil and rewind it with enough turns to reach the desired impedance with the slug set to it’s mid value. Then try it in the radio. If this is too complex (you do have infinite amounts of time on your hands, don’t you?) you could rewind that portion of the coil by carefully unwinding the coil while counting the turns. When rewinding, it will be important to use wire of the exact same gauge. I’ve used this counting technique with success on several occasions. I hope this helps.

    • Brian Denley KB1VBF
      July 20, 2014

      Do you offer SX-28 restorations as a service? I have one that I have been keeping for several years trying to get up the courage (see my website). It’s in very good shape and works but the AVC is not working, and with it, the s-meter. How much does an average restoration cost?

      And if you don’t do restorations for people do you know anyone who does?

      Thanks
      Brian Denley KB1VBF
      July 20, 2014

      • Thomas
        July 21, 2014

        These things are usually a labor of love for the owner. The SX-28 restoration is very do-able, but it takes more time than most. A full restoration and alignment would take 40 to 100 hours (perhaps more, if an oddball problem was encountered), so it would be impossible to charge fairly for the time spent. There is, however, a directory on the CHRS website of people who repair radios. You could ask them to address the AGC problem you mentioned, but if you don’t do a full restoration, you’re likely to encounter another problem soon. The paper and electrolytic caps in these receivers are all prone to failure at this age. That said, I highly suggest you tackle the restoration yourself if you have the skills. I’m busy, so my restoration took me about a year. The SX-28 is one of my most prized radios. It sounds as good as it looks.

    • ron hathcock
      March 25, 2015

      I also have undertaken a sx28 restoration project having problem identifying the two resistors above the 5z3 socket. Could you identify them
      thanks
      ron kdfea

      • Thomas
        March 25, 2015

        Trace the circuit and use a schematic diagram to determine the correct resistor value.

    • ron hathcock
      March 26, 2015

      Is there any diagrams out in radio land that names and part identification. I have a sx28a that was cut up pretty bad would like to repair it
      thanks. I do have manuals for the sx28a but the manual does not show part locations

      ron hathcock kd4fea

  2. Mike Adams
    December 19, 2012

    Hello Tom, I used to have one of these but my technical skills are not deep enough to do what you did. I am impressed with your knowledge! And patience! By the way, I also had another Hallicrafter’s communication receiver, but this one had in addition to the usual tube lineup several acorn tubes. Could it have been an SX 27? It actually worked.

    Mike

  3. Michael pacinda
    June 28, 2013

    Hello, a older gentleman was moving out and was throwing away a ton of stuff….tools,fishing idems and one of the idems were a hallicrafters SX 28 radio…..nice is it worth anything and could i sell it….it weights a ton …..hahahah…..thank you….michael

    • Larry Young
      July 21, 2013

      Michael, has this question been answered? SX-28’s range in value depending on the type and condition, roughly $300 on up. A complete unit in need of Restoration would be worth $400, but the cost of restoration may run near $1000 and that may is in consideration that the cabinet is not all scratched to heck and the internals not corroded such that they are unattractive. About four years ago I paid $650 for a restored complete SX-28 the type with the screw on RF cage cover. The radio only needed thorough cleaning on the inside and that took hours. Restoration of the paint is a problem in matching the crinkle effect of the paint. Weighing in at 80 pounds shipping and handling to someone for restoration adds to the cost of shipping and the restorer… make sense? Since these radios are becoming rarer they warrant protecting, so if you are not game to get it fixed-up be sure to get it to someone who is. LY

      • John Gadeikis
        July 30, 2013

        WOW! Beautiful radio you have there. My grandpa had a Knight Shortwave set when I was a kid. I remember him always fiddling with it. These vintage units are really well made and that’s SO obvious with your Hallicrafters, which was a very popular brand name back in the day. With updated components your unit should really work nicely. I’m into the Fisher FM receivers from the early ’60s. Best of luck to you with your really cool Hallicrafters.

    • John Gadeikis
      July 30, 2013

      Michael Pacinda,
      Do you still have this radio? I’m wondering…Please post reply.
      Thank you,
      John

  4. Rob
    October 15, 2013

    Looking for someone near California who can do a restoration on my SX-28A cabinet. I’m down in Monterey. I bought this at the auction earlier this year.

  5. Joe P
    November 16, 2014

    Hi All.. I enjoyed reading your posts. Thank you all for the info. My daughter bought an six 28 a at a local hamfest and I am helping her restore it. We just completed replacing every paper cap we could see; and still have about 12 to go. Thank you for the tips!!

    73 for now
    Joe P k3fe

  6. Joe p
    December 19, 2014

    Hi all
    We completed the recap job, and the sx 28 turned on. The amp works fine but still has some 60 hertz hum we have to find. Found some sort of mod in the S meter circuit while looking for the source of our hum. We plan to remove the mod than find the hum. This mod has connections to many locations in the receiver and I am not sure if I have the correct print for the sx 28. Does anyone have any pointers on proving that I am using the correct print. I have a couple of similar prints.

    Thank you for the help
    73
    Joe k3 fe

  7. Steve N2IC
    February 14, 2015

    I just came upon an SX-28A, unrestored. It works, but it’s missing the louvered, clip-in, condenser cover. Anyone have a source for one ?

    Thanks !

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