Friday, February 1, 2013

Boatanchors!

Boatanchors....I LOVE Boatanchors. No, I am NOT talking about the big, old, ugly thing that sailors drop over the side of their boat/ship to secure it's position when not in motion. I AM talking about those old pieces of vacuum tube radio gear that are extremely heavy (due to the transformer/inductor "iron" included on their chassis to convert AC into DC and rectify RF into Audio, and convert Audio into RF). One of the most iconic Boatanchors is the Heathkit DX-100 AM/CW transmitter, which weighs in at around 100 pounds! Seriously, I had one in college and it was a MONSTER! Glad I didn't have to lug it up a couple of flights of stairs to my room.

Over the intervening years, I have restored countless Boatanchors and the thrill of seeing an old radio, whether it be a receiver, transmitter or transceiver, come to life after a restoral/rehab is absolutely unbelievable! For you see these old radios have a story...a history....one that cannot be told by sitting on a shelf or floor in an inoperable condition. They have to "sing". They need to be set free and made to work again after years of neglect. Yes, I am an incurable romantic....not only that, I truly believe that these old rigs have a personality and they actually "speak" to me. To fix them up and make them work again is a special gift I have. I am not alone. I know others that share my passion for Boatanchors. All of us Boatanchor Enthusiasts have a special calling. We are "radio whisperers", if you will. We speak for the radios, and when we complete a restoration or rehab, they can then speak for themselves. Like I said, it is a calling.

OK, now that most of you think I am certifiable, let me assure you that I am not. Boatanchor restoration takes an extraordinary skill set; a unique ability to see beyond the rust, corrosion, butchered modifications and look deep into the soul of the radio. It takes a special dedication to take a cast off piece of radio gear and put in countless hours of work and dollars of personal expense to get these old radios back on the air. It is definitely for the love of the hobby.

Oh, did I mention that the voltages inside these old metal monsters can kill you?? YUP, shore can! Took almost 1000V across my left hand one day in the Azores from an old Collins transceiver! Thankfully I was not holding onto the microphone with my right hand, or that 1KV would have gone in my left hand, up my left arm, through my heart, and out my right hand, most likely killing me stone cold dead right there in the shack! One must be careful when working on these old rigs, that is for sure.

My current Boatanchor restoration centers on a R.L. Drake 2B communications receiver, circa 1960. I remember when the 2B was "the receiver" to own. It was state-of-the-art at the time and, for a paltry $279 (in 1960 dollars) it was a great deal! Interestingly enough, you can purchase a 2B on e-bay or at a ham radio website for around $250, which is not too far off the original MSRP. (of course the dollar adjustment between 1960 and now is substantial but it does prove how well this receiver has held its value)




My 2B came to me by way of a ham down in Texas. I have purchased several radios from Gary and know him to be a very honest and upstanding ham radio operator. This 2B came with the optional 2BQ, Q-Multiplier/speaker housing. This accessory increases the selectivity of the receiver tremendously by adding a regenerative stage into the IF strip of the 2B. By setting the 2BQ just before oscillation, the 2B has a razor sharp IF strip that reviles today's high end solid-state receivers/transceivers!

Initially, the only thing wrong with this receiver/Q-Multiplier combo was some rubbed front panel markings on the BFO and Product Detector switches. Since this was only a cosmetic blemish I was not overly concerned. I used the 2B/2BQ for about 4 years and had a ball, pairing it with my Heathkit DX-60B transmitter along with a clone of the iconic AMECO AC-1 crystal controlled tube-type transmitter of the late 1950s. It performed flawlessly and I had a lot of fun with this radio.

 

However, shortly after Straight Key Night (SKN) in January 2013, the 2B started exhibiting an inordinate amount of audio (AF) distortion. The distortion was present without regard to the settings of the AF or RF gain control or the settings of the BFO/Product Detector switches. This indication has led me to the conclusion that the distortion could be traced to the cathode bypass capacitor on the AF amplifier tube (a 6AQ5) or possibly the biasing resistor or coupling capacitor on the same stage.

I have joined the Drake group on Yahoo (http://groups.yahoo.com/group/DrakeRadio). What a bunch of GREAT hams. Seriously, these guys have provided me with a ton of information on where to go from here on the 2B. Garey Barrell, K4OAH, is the group moderator and he offers a service for fellow Drake owners/restorers: a series of DVD/CDs that are rig specific, showing detailed color high quality digital pictures, labeled with each and every component. In addition he includes the operations/service manual(s), modifications, schematics, etc. The CD for my 2B cost only $20 which included first class USPS shipping! I had it 3 days after I ordered it and what a great source of 2B info! If you have a Drake radio you are in need of upgrading, restoring, or troubleshooting, I strongly urge you to contact Garey at www.k4oah.com and pick up a CD for your particular Drake rig. You'll be glad you did.

Tom Farland, N0JMY, at Hayseed Hamfest Co., (sales@hayseedhamfest.com) offers several unique services for the Boatanchor restorer. Tom's primary line of parts centers on multi-section electrolytic capacitors to replace the leaky power supply caps in an old radio. Over the years these electrolytic power supply caps become "leaky", which means they no longer function as intended and allow 120 cycle hum to become prevalent in the radio. Nothing is quite as irritating as that constant 120 cycle hum on the receive audio in a receiver. Replacing the main power supply electrolytic caps can be problematic, since replacement caps are not exactly a stock item at Radio Shack! Tom manufactures extremely high quality multi-section caps that are exact physical replacements for the original PSU parts. Tom's prices are very reasonable, the replacement for my 2B PSU electrolytic (a 4 section device: 100 microfarads @ 200VDC X 2 and 10 microfarads @ 200VDC X 2) cost about $30.00 plus a couple of bucks for USPS shipping. This is an exact replacement for the stock Drake cap and is made with modern techniques, so it's just not a NOS (new, old stock) part that is 40-50 years old! Tom offers replacement caps for Heathkit, Drake, Collins and other Ham Radio gear, so if you are in need of a power supply rebuild, I highly recommend you drop by Heyseed Hamfest and check out what Tom and his wife Julie have to offer.

Right now I am in a holding pattern awaiting the arrival of these and other parts before beginning the electrical rebuild of my Drake 2B. Aside from replacing the main PSU electrolytic (Heyseed Hamfest) and several other capacitors in key places) and doing some routine voltage checks to isolate the stage(s) that are inducing the AF distortion, it should only take about 4-5 hours to complete this electrical restoration.

Of course, just replacing some caps and possibly some out of tolerance resistors would be meaningless without doing a complete re-alighment of the receiver RF and IF stages. this will take another 3 or so hours, to do it correctly.

As long as I have the radio out of its case, I will be re-painting the case and will attempt to get a vinyl overlay for the front panel to spruce it up a bit and be rid of the rubbed lettering on the original painted panel. This is another service Tom, N0JMY, offers. He started doing vinyl overlays for Heathkit HW-16 transceivers a few years ago and has branched out into other radio gear. According to Tom, a new vinyl overlay for my Drake 2B will cost about $35 and he and Julie will apply it to the panel if I will send the panel to them. Can't beat that price! I received a quote from another source who offered to re-silk scrreen my 2B front panel for $110...on top of an additional $150 to cover costs of making the silkscreen mask, mount it and get it ready to use. No thanks....for that kind of money I can obtain another 2B!!!

More on this restoration as time allows.

Vy 73

Rich K7SZ















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