Updates for the station...


It's been a while since I've updated my ham radio page. The last year has been a significant time of change for me. I retired in July 2013 from employment and that has given me more time to participate in amateur radio and other activities. Similar to other retirees, I sometimes wonder how I had time to work...Hi-Hi. It seems I have no shortage of projects and things I need to do!  Since my last post, I completed the Yagi antenna installation on the crank up tower. The HF antennas are working well and I recently confirmed enough HF DX contacts to qualify for DXCC.  I now have 116+ countries confirmed on the ARRL's logbook of the world. My long term goal is to achieve DXCC honor roll using only LOTW confirmations. This year, I have been focused on working the ARRL Centennial portable operations as a year long goal of achieving worked all states (WAS) using only ARRL portable contacts.   Once I complete the contacts I need for WAS/W1AW, I plan to apply for both the WAS and DXCC awards. 

During the past several months, I've completed a few ham radio projects that were pending on my “to do” list. First, I renovated my workshop that is located in another area of my home to make it more suitable to perform tasks on ham radio/electronic projects. It's in that area that I build and repair my ham radio equipment. During the period, I also built additional shelving for my operating desk, and refined the switching matrix for my station to handle the multiple transceivers and amplifiers I use. The station is now much more user friendly, as there are no cables to physically move to bring a radio or amplifier on line. The switching matrix is handled by 5 switching devices (3 antenna switches, a data/microphone switch box, and a switch box I built).  In the future, I would like to consolidate all switching tasks into a custom assignable modular design.  That may be another project I might tackle in the future. 

In the station, I have a Kenwood TS-830S that I use occasionally and use a Kenwood DFC-230 solid state frequency controller to stabilize the VFO on the 830.  However, recently the DFC-230 began to act erratically. Due to the age of the DFC-230, I thought it would be advisable to begin with replacing all of the capacitors. Apparently, some of the capacitors were defective, because the DFC-230 began to function normally once it was recapped. Total cost was around $12.00 for the update.
Another project I completed was to replace the capacitors in a 1947 Philco Audio/RF Signal Generator. Recently,  I had been looking for a signal generator, and this one was offered to me at a very good price by my friend Reid W2HU.  Some of the test gear from the 40's and 50's are a work of art.  The metal work quality on the 1947 Philco is outstanding, and certainly surpasses anything produced today.

Recently, I also added several new transceivers and a vintage amplifier to the station. The amplifier is a Drake L-4B to use as a companion to the Kenwood TS-830S. The L-4B is in very good physical condition. When purchased, the inspection tag was still attached to the amplifier, and showed a build date of June 6, 1977. As a statement to the durability of the Eimac 3-500Z tubes, the amplifier still has the original 1977 date coded Eimac tubes still installed and making full power!
IMO the Drake L-4B has one of the better RF decks built during that era. However, the amplifier does have a few design deficiencies that IMO should be corrected, and had age related issues as well. Therefore, I decided to modify the amplifier to resolve those issues and to also update the power supply.  To update the power supply, I installed a new power supply board that included all new diodes, resistors, and capacitors. The new board eliminated the two separate capacitor boards and added additional capacitance as well.
The design problems with the L-4B are twofold. First, in it's stock form a surge from the high voltage power supply flows through the HV switch on the front panel whenever the amplifier is switched on. After years of use, the HV switch on the L-4B has a tendency to burn and fail, and a replacement switch is not readily available. The second issue is more common. Similar to most vintage tube amplifiers of that era, they have a considerable amount of voltage and current involved with the T/R switching relay. Many modern transceivers are unable to handle the high switching voltage without using an external padding device, or will sustain damage that is usually expensive to repair.

To correct those issues. I first modified the on/off switching circuit by installing a vacuum relay to handle the HV switching.  The high voltage is now handled by the vacuum relay and the front panel switch now only handles a mere12 volts and 30 mils of current. The second modification I installed is a small optical keying buffer. That circuit now handles the internal higher voltage T/R switching and thus the transceiver only has to sink to ground, a low power/current signal to place the amplifier into transmit.

I am always interested in new equipment that will place the most SSB contacts into my log.  I recently acquired a Yaesu FTDX-9000mp that includes the 400 watt PA and decided to put it to a real world test against a IC-7700 I also had in the station.  Testing in my station indicated that there was no significant difference in performance between the two for performing weak signal SSB reception. Therefore, I decided to sell the IC-7700 with the intention to purchase another rig at a later date that was more recent in design and may have a better receiver.

The next rig purchase was a Yaesu FTDX-3000.  I discovered that its performance was very close to that of the FTDX-9000.  However, operationally the FTDX-9000 is far superior for my style of ham radio, because the FTDX-9000 series is less menu driven for basic operation settings.  Although the FTDX-3000 is a great radio, it still did not add anything significant to my station's capabilities.

The most recent purchase is a Kenwood TS-990S.  I've only owned the TS-990S for a relatively short period of time. Nevertheless, in relation to weak signal SSB work, the TS-990S has proven to have better performance than the FTDX-9000.  It took Kenwood nearly 11 years to produce another flagship radio, after production ceased for the TS-950SDX.  I am please with the TS-990S and can say the wait was well worth it.  I have written E-Ham reviews about both transceivers and they can be read here.

FTDX-9000 http://www.eham.net/reviews/detail/7862

Vintage Hybrid Station; Astatic D104 Microphone; Kenwood TS-830S, DFC-230, SM-220; Drake L-4B, L-4 PS; Ten Tec 1225 Peak Reading Power Meter...

Current main HF operating position...