HR-10b Project

Discussion in '"Boat Anchor" & Classic Equipment' started by W7UUU, Feb 13, 2016.

ad: L-HROutlet
ad: l-rl
ad: Left-3
ad: abrind-2
ad: Left-2
ad: Subscribe
ad: L-MFJ
  1. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    One of those "looks really nice and works great" things - completely dead after purchase - we all know the story :)

    I acquired this to pair with a DX-60b / HG-10b combo to replace my venerable HW-16 that has earned its place on the shelf after completing W.A.S. and about 33 DX. Only have so much room - so the HR-10b/DX-60b + the ever-so-rare Heathkit HC-10 console will hopefully occupy that space.

    While awaiting parts for the very unexpected Drake 2NT "uh oh - she died!" project (see other thread!) I figured "no time better than the present" to test out the HR-10b and start a PS recap project. Let's just say I'm really glad I ordered the 20/20/20 cap kit from Hayseed a while ago... ugh. TOTALLY dead other than a dull 60hz hum - not very loud - "Works great" not in evidence.

    Here she is at the "let's put her on the Variac and see what she can do" setup (yes, I know "wrong knobs" - I have plenty of correct knobs that will go on after the repairs) :

    HR10 1.JPG

    After a few hours of slow "Variac Time"... nice glow anyway :)

    HR10 2.JPG

    After initial testing with utter deadsville - just a low hum, I knew it was HW-16 stuff all over again. So I put her on the bench - the actual construction is pretty nice! Good soldering, nice layout, good mechanical stuff - yay!! Glad to find all that.

    But someone had done an antenna jack mod (RCA to SO-239) and I don't think that long ago - the SO-239 is pretty modern looking, not a vintage silver-plated jack - good quality but not vintage stuff for sure. Just HORRIBLY done - solder joints so cold they pretty much broke off as soon as I touched them.

    More pix and stuff in a sec... sometimes this software times out and I lose all I've done

    W4NNF, N7ANN and WA7PRC like this.
  2. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    Here's the yucky SO-239 mess that fell apart the second I touched it - note the SO-239 sort of "cross-threaded" into the jagged hole... note that that red hookup wire is like 6 inches long and is the shield connection for the coax to the SO-239 that was added, with a cold solder joint to anything it touched as well as the coax center wire to the SO-239 - fell apart when touched - yet note the quality installation of the 1k resistor and the bypass capacitor - surely not the same person involved in both tasks:

    nasty1.JPG nasty2.JPG
    Last edited: Feb 13, 2016
    WA7PRC likes this.
  3. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    So before tackling the bigger issue of the PS cap I figured I'd sort this mess out first - I installed a terminal strip on the calibrator socket screw, replaced a broken .005 uF bypass cap (darker one here is the new one), properly drilled out the SO-239 hole in the chassis, replacing the janky "whatever I could find" hardware with 4/40 stuff, and retrimmed the coax for the RF feed.

    Looks a lot better and now at least the SO-239 is properly done, IMO.


    Cleanup 1.JPG
    N2EY and WA7PRC like this.
  4. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    So for tomorrow, the filter cap project - easy-peasy - just quite a number of connections to make note of but will do in the fresh light of a new day :)


    Capacitor 1.JPG Capacitor 2.JPG
    N7ANN, N2EY, KE5OFJ and 1 other person like this.
  5. W9GB

    W9GB Ham Member QRZ Page

    Know this receiver ... I built it in 1972 (high school electronics).
    Learned Vacuum tube & Point-to-Point wiring, and good soldering.
    Good for 80 and 40 meters, so-so on 20 meters, largely deaf on 15/10 meters.
    The 8-pin octal socket is for the HRA-10-1 plug-in crystal calibrator, these appear often at eBay, reasonable price.

    QRZ Q&A Technical Forum (2008)
    The SO-239 was a "bad hack" ....
    IF RCA not desired (they work fine, cheap, widely available),
    the BNC is the preferred NO Hack change.
    K6JCA article
    Electric Radio Magazine Articles:
    • "Resurrection of a Heath HR-10B Receiver," Paschall, Issue 210, Nov. '06
    • "The Heathkit HR-10 Receiver," Hanlon, Issue 232, Sept. '08
    • "Heathkit HR-10 Receiver Update," Stock, Issue 234, Nov. '08
    • "Modifying Heathkit Crystal Filters," Stock, Issue 231, Aug. '08
    Many mods add a voltage regulator Your Heath HR-10-11-72.pdf
    Last edited: Feb 13, 2016
  6. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    Thanks GB! I do in fact have the calibrator - safe and sound along with all the HR-10b tubes in a separate bin on the bench. Yeah - I figure it's only going to be an 80/40 deal - but I'm encouraged to hear it's at least "so-so" on 20m - to have any chance at a W.A.S. with it (always my goal with any new rig) I'll need 20m so I can use the beam.

    I will also look into the mods - thanks for the links. I always really appreciate the effort you take to research topics of threads and post links and stuff like you do - your efforts make this place a better community.

    KD2ACO and KC3BZJ like this.
  7. AD4U

    AD4U Ham Member QRZ Page

    After hamming over 50 years and "working them ALL" I looked for a new challenge. 5-6 years ago I put a Drake 2NT and 2B on the desk and started working 40M CW exclusively into a dipole up about 60 feet. So far I worked 293 countries on 40M CW with this 50 watt crystal controlled transmitter and a 60 year old tube type receiver.

    Wanting another challenge I recently bought a HR-10B and a DX-60B. Like yours, mine needed some work. While the HR-10B definitely is no Drake 2B in performance, mine works quite well on 40M CW. I can "hear" a 0.1uV signal on 40 and the HR-10B is quite stable after a warm up. Selectivity is poor at best.

    So another challenge has started. So far using only the HR-10B and the DX-60B I have worked 47 countries this winter. I have a long way to go to match what the Drakes did. Due to the limitations of the HR-10B I may (or may not) stop if I work 100 countries.

    It does not take a modern $10,000 rig, 1500 watt amp, and a yagi at 100 feet to work lots of DX.

    Dick AD4U
    WD4IGX, N7ANN, KL7KN and 4 others like this.
  8. W9GB

    W9GB Ham Member QRZ Page

    Yes, that's true.

    The HR-10B is a single conversion receiver (1681 Hz, IF) that uses 2 crystals for a half-lattice filter between IF sections.
    That IF was popular in WW2 (BC-455 used 1415?) and some 1950s receivers.
    Hallcrafters SX-140 (inside view)

    I always suspected that the HR-10B was heavily influenced by the Hallicrafters SX-140 (1960-1965), across Lake Michigan (Chicago), which used the same IF.
    I think EF Johnson Messengers (CB service in early 1960s) also used that IF.
    Bill Orr had a great Product Detector (1959 Radio handbook and later) that used the 6SJ7 Octal tube.
    In late 1970s, I drew out a schematic to replace the 3-diode (9-pin) vacuum tube with a suitable 9-pin version of 6SJ7 using that Orr idea (using solid-state diodes for AVC and ANL function.

    Dallas Langford spent considerable time on product detectors.
    Last edited: Feb 13, 2016
  9. W9GB

    W9GB Ham Member QRZ Page

    Last edited: Feb 13, 2016
  10. KX4OM

    KX4OM Ham Member QRZ Page

    My sympathies on the hack job of the SO-239 connector. I've got four HW-xx single banders, and one that has a decent board and OK chassis has this rear panel. This might be a JBWeld fill-and-sand repair with a plate with the correct lettering on it.

    Ted, KX4OM

    Attached Files:

Share This Page