First off, this is a fully operational transceiver! I have had it on the
air during December of 2004 on both AM, SSB and CW. I received great audio
reports in both phone modes. One of my SSB checks was on 15M SSB where
I talked with Roger G3MGW who was located 100km northeast of London. This
was using my 80 meter double-bazooka through an antenna tuner.|
I was able to get over 100 watts out on 80 through 15 meters and around 80 watts on 10 meters. This meets the spec requirements. Sensitivity meets the published specs as well.
What I did to the radio:
1. Lubed mechanical links and gears.
2. Cleaned the TR relay contacts. Originally the S-Meter was intermittent. The meter functions as an relatve RF output on transmit and the S-Meter function on receive. This selection is made through contacts on the multipole TR relay. Once the contacts were cleaned the S-Meter worked flawlessly from that point forward. The contacts were cleaned by polishing using paper strips cut from a standard brown paper grocery bag. This is the best method I've found and it is not abrasive enough to damage the contacts.
3. Recalibrated the PTO's. Set the PTO to be dead-on at the center of each 500Kc bandspread. Overall deviation is within 2Kc at either end. The internal calibrator allows setting the sliding pointer, above each PTO dial, to compensate for any linearity errors. You simply calibrate the pointer to zero at the nearest 100Kc marker point and you will stay within 1kc (easily) over the 100kc range. During my PTO calibration I discovered the the Blue labeled PTO was most linear across the full 500kc bandspread. Maximum deviation was 1.5kc from the calibration point. The Red labeled PTO was measured at about 3kc, or double the error of the Blue PTO. This really is pretty good considering the bandspread is 500kc and the the user can recalibrate on-the-fly at each 100kc marker. There are linearity adjustment located within the PTO's, but I don't consider the current linearity worth the effort nor time to remove them and make the adjustments. Plus, I'm of the school that "if it works well, don't mess with it". The rarity of this radio does not allow for finding easy replacements for broken parts.
Stability was excellent. Remember the PTO's are all solid-state, unlike the PTO's in the Collins S-Line equipment. I didn't make up any stability curves, but I do know if I turned it on a let it warm up for about 15 minutes I was able to hold long QSO's on SSB without having to touch the tuning knob. Pretty much the same experience as using my other PTO rigs. i.e. Drake and Collins.
What I DIDN'T do to the radio:
1. I did not replace one component! That does say a great deal about a forty plus year old unit. Capacitors are all ceramic disk or dipped silver mica in the RF & IF signal paths. Bypassing are high qualitity MEC brand encapsulated. Even the electrolytics reformed just fine.
Hallicrafters chose well when determining component source and types used. No Black Beauties in this radio!
2. I didn't shine or wax anything! OK I did wash the front display window with warm soapy water to get the finger prints off. Inside its extremely clean. All the PCB's are tin plated and from day-one seem to have lived their lives under good environmental conditions. You'll see in the PCB pictures that maybe they have lost their initial shine, no major oxidation has occurred anywhere! I own five year old equipment that look worse. This radio does have some cabinet nicks and scratches. Again, nothing major and to be expected from a radio that really saw operating in it's time.
3. There is a scratch on the front panel from the band switch knob. Like many radios the users and sometime the manufacturers will mount the knob on the shaft to close to the panel. That's what happened here! I've included a picture that shows this scratch to the front panel. Since the front panel is chromed I opt'ed not to attempt any restoration or removal of this scratch mark. For the most part it isn't deep as it really hasn't even destoryed the front panel markings which it runs through. For me this is the only major cosmetic damage that this radio has!
4. The interconnection between the power supply and the rig is one cable that terminates into a large multi-pin (military Cannon type) connector. The connector has both RF (Shielded) and DC pins which are silver plated. After all these years the silver plating is tarnished. I did not clean the tarnish off as it will return relatively fast and silver tarnish is highly conductive. Removing the tarnish would only make things look better, if the cable was removed, and would not make any improvement in operation.