A couple years ago, when I wrote the "I Had a Dream" article, I was waxing nostalgic about how, back in the 1970's, our budding CB group of young teenagers often sat in awe of what we called "Dream Rigs", those radios which seemed larger than life, and equally unobtainable due to their inordinately high price tags. At the top of that prestigious list, were the Browning Golden Eagle, and the Tram D201, each running about $750 in 1975 dollars. Running in the third place spot was the Hy-Gain 623, which topped the cash register at $595. Not many people, in my working class area, could afford such high dollar radios (although there were a couple who did own Hy-Gain 623's), and because of this, these rigs often took on surrealistic and near mystical qualities. It was almost as if running a Tram or a Browning would open up all doors to long distance communications, make you the talk of the channels, the object of envy which may even land you a hot date to the next CB coffee break. Yea ok, so we did have a habit of going a bit overboard back then. After all, none of us are perfect. But despite our distorted impressions, those truly were the rigs that people longed to have, even if their paychecks (or paper route money) didn't leave enough extra to afford. Most of us surrendered to our fate and went ahead with our lives using our "working man's radios", never having had the chance to know what it was like to command the top of the line CB radio of the mid 1970's.
Fast forward 30-some years. The tacky fads of the 70's faded into obscurity and gave way to equally bizarre styles like the mullet in the 80's, along with the death of really good rock music. The 80's quickly melted into the 90's and by then, those of us who were still involved in the radio hobby were all running much more modern computer controlled solid state ham or export radios, which could tune most (if not all) of the 11 meter band , had much more power out, and had the additional mode of FM along with them. We had marched ahead with technology, and didn't much think about those old tube rigs. But then something happened when I entered the new millennium. This may have had something to do with reaching that "big 4-0" milestone, a shift of hormones, the appearance of gray hair, or the awareness of my own seemingly rapidly approaching mortality. Whatever the case, I've become increasingly retrospective of many aspects of my life. And since there are many great memories from my teenaged days in CB radio, it's no surprise that I would focus heavily on that part of my life when tripping down memory lane. So as a consequence, I've been revisiting that longing for those rigs of yore. Those mighty base station radios that we all wanted, but couldn't afford. I have been slowly amassing a fairly good collection of the radios which had influenced me to some degree. Most can still be found long forgotten in the attics and basements of old timers, at hamfests and on on-line "for sale" sites, like E-Bay. Most of the more common radios can be had for fractions of their original selling price (I bought a really nice Royce 640 for $10). But the top dogs on the dream list, those elusive Trams and Brownings, are still, even after 30 years, commanding a premium price on the auction block. Now I don't mind throwing around $10 here and $20 there, but I'm not about to pay $200 or $300 for a 35 year old radio that, in all likelihood, will need a good bit of work to get back into prime operating condition. So my dream still seemed to be a step or two out of my reach. However, a wise person once said to me that good things come to those who wait. While it didn't happen overnight, that patient waiting appears to be slowly paying off. First, I managed to score a Hy-Gain 623 from my old friend and mentor Blue Bandit back in the late 90's before I even knew I'd start collecting old rigs in earnest. Then, a couple years back, a Tram D201 landed in my possession courtesy of Art. It was a wonderful experience bringing that old tired dog back to life. Now all I needed to make the premium rig collection complete was a Browning Golden Eagle. But I wasn't holding my breath. If anything, the Brownings were fetching even more $$$ than the Trams. But my patience was about to pay off once again.
In early January of 2008, I was contacted by the moderator of a CB radio forum that I frequent. He, unfortunately, has been dealing with poor health and had been selling off much of his classic radio collection. He offered up his slightly ailing Golden Eagle Mark III to me, knowing that I was always looking for classic rigs. Of course I was interested, but I figured that he'd want way more than I could afford to spend (I was still reeling from post Christmas sticker shock). I replied that I could only afford about $75 for it (which was $25 more than I actually had on me at the time). I expected him to balk at my measly offer, but to my surprise, he accepted it! Yahoo! He told me that it would probably need some work, but I didn't care. In fact, I like a project radio, remembering how much fun I had restoring the Trams the year prior. I wasted no time picking the Browning up. Truth be told, I didn't want to risk him changing his mind, or casually mentioning it to someone else, who would then whip out $200 cash and take it right there. It wouldn't be the first time THAT has happened to me. But no worries, I got the radio, which also came with a G-Stand unamplified D-104 microphone. The first thing I noticed when I unboxed it was that it reeked of stale cigarette smoke. Being a non-smoker with adult onset asthma, makes me ultra-sensitive to it, so the first thing I had to do was wipe it all down inside and out with a little cleaner. I managed to dull, but not eliminate the odor, but at least it's not overwhelming. I also gave the rig a good visual once-over. I noticed that the receiver's main multi-gang filter cap was bulging at both ends. That didn't look too good, so I cut it out of the circuit and bypassed it with new caps. The caps that I used were higher in capacity than the originals, so when I fired the rig up, I noticed that some of the voltages were running a little high, so I may have to make some adjustments later on. The good news is that the receiver has absolutely no hum at all and the tuning dial seems to be spot on, at least on the CB band. A previous owner had also added an extra crystal so there are 3 bands to receive on. The bad news is that the sensitivity is a little weak. Even after a good alignment, I could do no better than about 2uV for 6db S+N/N, and the "S" meter reads improperly. There is no meter adjustment, except a meter zero, but a 50 uV signal, which would normally read at an S9 level, pushes the meter to +30db over S9. Both of these symptoms could be a sign of weak tubes, or out-of-tolerance parts. Time (and further work) will tell.
The transmitter was not without issues either. A handful of the crystals are way off-frequency. The previous owner used an external VFO because of it. By some stroke of luck though, channel 21, one of the channels I use the most, is one of the good crystals. Unfortunately, channel 13, home of Classic Radio Roundup and another frequently used channel, was about 3 khz low. Placing a trimmer in series with the crystal allowed me to correct the error though, so I gave thanks, wiped my brow and moved on. The transmitter worked well on AM, with over 3 watts of carrier power with good strong modulation. Although I had to swap heads from another one of my D-104's, as the one that came with the Browning was nearly dead. The worst news came when I switched to SSB and found that the transmitter was completely dead. Not even a whisper of signal came out of it on either SSB mode. So it looked as if I had the lion's share of my work yet ahead of me. The downside to this is that the transmitter was usable as it was for local AM chatter so I've been using it rather than exerting the effort to correct what's wrong. But I guess it's understandable. It's not everyday that someone finally comes face to face with one of their childhood dreams.
The next day, I made a little progress in determining what was wrong with the SSB portion of the transmitter. Initially I had surmised (feared actually) that the balanced modulator diodes were kaput. I have heard of this happening before, so it was fresh in my mind. The problem with this is that the diodes are contained within one of the tuning cans, and access would be difficult. But once I got the scope out and started probing, I found that the BM was passing a modulated suppressed carrier signal all the way to the crystal filter. So I am feeling some relief. At this point I'm starting to see some discrepancies between my radio, and what's depicted in the schematic. So I'll have to see if there are multiple revisions of the MK III transmitter and finding out which one I actually have.
The next day turned out to be a quantum leap forward in progress on the Browning. I dug out the spectrum analyzer and, using a scope probe attached to it, I began signal tracing the transmitter to see what was not working on SSB. It didn't take long before I realized that the 5 Mhz carrier offset crystal oscillator was only working in the AM mode. Hmmm.... What are the chances of having two bum crystals? So after looking at how the crystals were attached and comparing to the schematic, I realized that the USB and LSB crystals were connected incorrectly. They were attached across the trimmer caps rather than one lead soldered directly to ground as called for in the schematic. Someone had obviously been playing around in this section before and fouled it up. I corrected the crystal connections so that they agreed with the schematic and voila!, the rig now transmits on all modes. A quick alignment and it's ready to rock. Speaking of rocks, I mentioned before that a handful of channel crystals are off frequency, but most of them can be netted in by inserting a trimmer cap between the crystal and the common rail. So as the smoke lifts, the Mark III's transmitter is working fairly well. I am missing one channel (10), but almost all of the rest of the channels are usable. Power output is now about 3.8 watts on AM, and just about 10 watts PEP on SSB.
Once the transmitter was squared away, work began in earnest on the receiver. I had noticed that I can change how the "S" meter reads by swapping out the I.F. tubes (6BA6's). This made me think that most of my remaining issues were likely the result of weak tubes. Ironically, with all the work I had been doing on old tube rigs, I did not have my own tube tester. But not for long. Another wheeling and dealing opportunity presented itself, where I swapped a Courier Centurion for a tube tester. So I tested all of my tubes and found none that were really weak, which seemed strange based on my earlier findings. I went through the radio up and down and all around and still could not seem to get the sensitivity to where it should be. The tough part was that the receiver was only slightly weak, so nothing really stood out as an indicator of a weak stage. I was about to concede failure and resign myself to just using the radio as-is, when I got a lucky break. Pete (Spitfire-441), one of our locals and a fellow classic radio enthusiast, had also obtained a Browning MK III. His radio had a different set of problems, and he asked me to give it a once over to see if I could nail down an elusive AC hum in the transmitter. But while I had his rig, I noticed that his receiver's sensitivity was very good, so I thought that if I did a side-by-side compare of sensitivity with my receiver as I injected signals, it might point me to the weak stage. Well, the result of my signal comparison showed me that my problem was in the RF front end, which consisted of 2 Nuvistor tubes in a cascode configuration, which normally yields fantastic receiver sensitivity. Naturally the first thing I did was to swap tubes with Pete's rig to see if that was it. Nope (It couldn't be that easy could it?). So I started looking at voltages, which were all good. Then I started testing or swapping out components in that area, with no change. Finally the last component I had left to check was L2, an 18uH choke who's function is to block the RF input signal on the grid of the front end tube, from being shunted toward the AGC feedback grid bias voltage. Well, chokes tend to not change value often and usually, if it tests at a DC short, it's probably good (If it's open, it's obviously bad). So I didn't think the part was bad, but I had nothing to measure it with to confirm the correct value. But I was now desperate. I didn't have another 18 uH choke, but I did have 2 10uH's that I put in series. Well, low and behold, the receiver woke up and came to life with sensitivity that was even better than Pete's. After seeing resistors open up without any visible signs of burning (the Tram), nothing surprised me any more. But I wondered what would cause a choke to radically change value (or short), without any visual signs of overload. I came to the conclusion that the radio was probably exposed to a lightning strike, which likely fused the choke into a dead short. But whatever the reason, the good news was that I was back in business, and I could now align the radio the proper way, which involves broadbanding for uniform sensitivity over the entire tuning range. Even after the broadbanding, the sensitivity was still better than .2uV. But I also noticed that the AGC action/S-Meter drive was very much tube sensitive. Since there is no adjustment for the S-meter sensitivity, I swapped tubes around until I found a set that put the S-meter at S9 for 50uV input. While the different tubes did not make a noticeable difference in overall sensitivity, they made a big difference in S-meter/AGC action.
So now I have a fully functioning MK III. It's one of my favorite rigs to operate. The receiver is sensitive and fairly tight. The receive audio is warm an not wimpy like a solid state mobile rig. Transmit audio is strong, even with an un-amplified mic. And, of course, there's that unmistakable trademark ping. The only sore spot with this rig, is operating on SSB. While the transmitter works well on SSB (even if the power out is a little low at 10 watts), the receiver BFO drifts, and the quality of the received signals are not on par with other SSB rigs. After talking to other Browning owners, I've been told that the drifty BFO was a common thing, and not necessarily indicative of a fault unique to my radio. Since most of the people I've known with Brownings, used them on AM, I tend to accept this as par for the course. But now that I've lived another childhood dream, and am the owner of both of the top rigs of the 70's, it's only natural that I would pit one against the other. Check out my shootout article where I pit the newly restored Browning against my Tram D201, to see which one of these larger-than-life giants of the CB world was really the king.