Friday, March 30, 2018
On Tuesday, March 27th, it just so happened that I was sitting in the street in my Spectrum Cable van, when the UPS guy came around the corner. After intercepting him, and running inside with the box from Tennessee, I ran downstairs into the subterranean shack here at the home QTH.
After cutting through the multiple layers of bubble wrap and tape (the last owner had it professionally packed at The UPS Store), my "new" HW-7 was sitting on my desk.
The first thing that jumped out at me was the smell, the brown hue, and the stickiness that screamed SMOKER at me. Normally, this is a point of contention for many, as it should be when purchasing an antique ANYTHING...but this rig was free. A little (no...a LOT!!!) of TLC, some Simple Green, and a gentle brush made the panels (disassembled from the chassis, of course) squeaky clean...and without ruining the lettering on the faceplate.
Next...while the radio was disassembled down to the chassis, I took about an hour and examined it for obvious modifications. Thankfully, there are FEW. One such mod was the replacement of the original power socket with one that appears to be from an HW-9. The original owner is an HW-9 enthusiast, so this isn't too much of a surprise. Next, on the power leads, a small value capacitor was soldered across the red and black. This, I believe, was added to handle voltage spikes...or at least that's what I have read elsewhere.
Further, a transistor socket was added to where the 40673 is placed. There must have been a reason for this...experimentation, perhaps.
I reassembled the cabinet with the exception of the top panel, just so I could observe the innards while I am getting acquainted with the antique rig...and just as the last owner said...it turned on, but didn't do much. So, I started with the obvious...how's the audio? Similar...no...IDENTICAL to other HW-7s I have owned, the quite pronounced microphonics of the CA3035VI were present. When the preselector is peaked, merely touching the knobs or cabinet makes the sound of tapping a microphone in the headphones. So...the ancient audio amplifier still works.
But what about that FET socket? Turns out that the original 40673 had been replaced with an "equivalent" device, but there was no life coming out of it. Since it was in a socket, I didn't bother with any test procedures...I popped it out, and inserted a BRAND NEW 40673 that had been given to me by my best friend, Keith WB2VUO.
A few turns of the VFO capacitor, and the old rig burst to life. LITERALLY. Just as I remembered from my last HW-7, 40m in the early evening was filled with stations, W1AW as well. This let me know that the dial calibration was CLOSE. It's no service monitor, but it's not bad. I listened to the CW bulletin and was pretty satisfied with the apparent lack of drift once the RX had warned up sufficiently.
Now the moment of truth: did the transmitter work? At just about 2.2 watts output on 40, the rig seemed to be in decent health, considering it had been in the shack of a smoker...AND...is as old as I am.
But once the relay clicked back over into receive, the audio was gone. Since the lid was already off, I touched the RX contacts with a micro screwdriver to bridge the gap, as it were. Sure enough, that sticky nicotine residue had found its way inside the rig, and gummed up the contacts. A few gentle passes with some thin, fine grit sandpaper cleaned the contacts up enough to make it operate as it used to.
Well...it's absolutely every bit of HW-7...complete with the lack of RX offset on 40m. The Heath engineers designed this radio with a glaring defect. There have been numerous articles and designs for adding RIT to the front end, but, I have NEVER been a fan of mods, especially in the HW-7/HW-8 rigs. Sure, they make it more usable, but being a purist, this is a non-starter for me. This radio is a toy. It is a shack accessory. It is a modest plaything...and it's also not my only radio, as the last one was post-divorce in 2013. So, the way around this for ME is to use the feature that attracted me to this radio when I was a Novice 30 years ago: the crystal transmit feature. Back in the 1970's, Novices were restricted to Crystal control. It was thought that the Novice needed operating experience, and dealing with a drifty VFO wasn't part of the FCC's plan. KC9ON sells FT-243 STYLE crystals. By STYLE, I mean that these are old school crystal cases with small form factor HC-49 rocks soldered inside. This will allow me to transmit on 7030...or 7055...or 7112...mainly SKCC Group frequencies, and perhaps a QRP calling frequency. With xtal control, I can use the RX and tune for signal. Sure, it's primitive, but I don't mind...it's a blast just using this old rig.
The transmit on 20 is ghastly. Tons of the classic "whoop-whoop-whoop" keying action. I suspect that the oscillator is a tad too sluggish at this point...perhaps some component replacement is in order...maybe a realignment. I'm not in any particular hurry to make it happen.
Well...the Reverse Beacon Network hears when I transmit, and the receiver is operating fairly well, for what it is. So that's 90% of the battle. She just needs some refinement...and some more cleaning...and new caps...and maybe some updated transistors in the TX section...
She's a time machine.