In the fall of 2010 when we came back to work, Allan, KX2H, Norman, KI4YSY, Bill, AG4PA, and Jack,WD4OIN, decided to concentrate on the TDE transmitter . It is our best operating transmitter, it requires very little warm-up time and has great tone sound. The generator for the TDE was mounted in the rear of the transmitter cabinet and on the floor on shock mounts. To say it was hard to work on was an understatement. The generator provides both high and low voltage for the transmitter.
We decided to pull the generator out of the rear and place it in front of the transmitter where we could work on it and take voltage measurements. This was accomplished by extending all the leads. Getting that generator out of there was quite a job. The sides of the transmitter had to be unbolted and removed so we could work the generator out of the side of the unit. We could tell that generator had never been worked on before , unbolting it from the shock mounts and taking the side of the generator loose was a big job. We had a lot of bruised and bleeding fingers before we got it out. I think of the ships crew doing this at sea on a rolling ship !
The generator must put out the low voltage which then excites the high voltage fields. We had no low voltage. With our limited generator knowledge we made all the tests we knew to make and could find nothing wrong. We consulted with the ship about the problem and they agreed to send the motor-generator off for repairs. In December of 2010 Norman and I carried the motor-generator to the shop in Rocky Mount, N.C. for repairs.
When we started work in January of 2011 we started to work on the TBM problems of which we had several, poor tone quality and low power output on some bands being the main problems. The tone quality problem sounded like maybe a filtering problem. For the next few weeks we worked placing capacitors across every capacitor we thought might be the problem, no luck. Power out on 40 meters was good, tone quality was a different story and we were running out of ideas.
Stumped on the tone problem for the time being, we changed gears and went to the low power output on 20 meters problem. We found that the power actually started rolling off a little on 30 meters and by the time it got to 20 meters it was way down. Power out on 40 meters and down was good. The crew had a brain thrust and started changing the tubes, one at a time. No luck at all !
Next we tried different ways of tuning the transmitter. While the transmitter has the ability to change frequencies it has to be retuned on all stages if you move the frequency dial much at all. Here again, no luck at all, back to the manuals. After much reading we found a paragraph in the old manual that said if you are using anything above 7 megacycles you need to use the final amplifier tube. The transmitter has the option of using the final tube or not. The drivers will put out about 120 watts into the antenna on 7 megacycles and down but moving up in frequency the transmitter response rolled off fast. When the ship was active it appears that it only used 7 mc and down in frequency.
Bottom line here, we think we don't have a problem with the output on 20 meters. With the final tube on, we still only get about 45 watts out but it looks as if this meets the specifictions on the transmitter. The tubes in these old transmitters have a bad high frequency response.
As the summer of 2012 is getting ready to start and we are getting ready to quit for the summer, we lose our final transmitter. When we fire up the transmitter one morning the motor-generator smoked. We found that we had lost one phase of the 3 phases to the motor.
At this point we called the motor-generator shop and checked on the TDE motor-generator which had been sent off earlier for repairs. It had a bad armature and they had shipped the armature to a Florida shop for rewinding. We told them of our other 2 motor-generator sets that was down and they said they would work on them. It's not everybody in the USA that will work on vintage 1939 equipment.
At this point we quit for the summer.
In the fall of 2012, we come back with a mess of problems. Again we consult with the ship and they agreed we would send off the remaining 2 motor-generators for repairs. Now all transmitters are off the air.
Now that we have some time we started looking at getting an antenna for the TBK transmitter. The first thing we done was put a tone on the antenna lead from the transmitter to the deck. We did't get the tone, no continuity from deck 03 to deck 1. For weeks we chase the problem and finally find that at some point the antenna conduits had been removed in the outer area of where the smoke stack goes up through the ship. It's like the flue in these modern day wood stoves, it's double lined and the conduits were in the outer area.
Now we have a real problem, how are we going to get an antenna ? We are interupped with the problem by our TDE motor-generator returning from the shop. We get the motor-generator down the 3 floors to the radio room and decide to hook it up in the isle to test it. The motor-generator runs and we have low voltage, we had none when we sent it to the shop, but we have low high voltage. It should be 2000 volts but we only have 1100 volts.
We call the shop and they said bring it back ! In early December we carry the TDE motor-generator back to the shop and started thinking things couldn't get any worse. Wrong, Bill Usher, AG4PA, who had been working with us since 2004 had a very short illness and became a silent key. Bill you will be missed !
In January of 2013 the other 2 motor-generator sets were returned from the shop. By the end of January we had all 1500 pounds of motors-generators sitting in place in the motor-generator room but the ships electrician would have to hook them up. As summer approaches the motor-generators have not been hooked up due to a heavy work load on the ships electrician but we have been working on the antenna problem. We were able to reroute the TBK antenna to another conduit and now have a good path from the radio room to the deck.
As we are preparing to quit for the summer, we have no radios working, we do have 2 motor-generators ready for hook-up and a path for an antenna for the TBK. The TDE motor-generator is still out for repairs. The trials and tribulations continue !