10 Meter Repeater RX Antenna rebuild...

This is a Hy-Gain Super Penetrator CLR2 antenna I picked up many many years ago for the 10 meter repeater. For years, I used fiberglass antennas alike the Big Stick or the Antron 99 for the repeater. After several lightning strikes on the 10 meter repeater sites, as well as strikes on the 2m and 440 repeater sites using fiberglass antennas like the Diamond and Anli antennas, I'm DONE with fiberglass antennas. It's a proven fact that fiberglass antennas develop a strong opposing charge on the shell as wind blows across them during a storm, making them a target for lightning. They're not so bad for side-mounted or low altitude installations. Stay far, far away from a fiberglass antenna for high altitude repeater installations, use only DC grounded metal antennas. 

The first step in this rebuild is to remove years and years of oxidation from the aluminum. I like to use Scotch-Brite pads for this. They easily remove the oxidation and really bring an aluminum antenna back to a nice shine. Disassemble the antenna and be sure to clean into all of the joints. Here's a quick pic of before and after on the 10 meter receiver's receive antennas, after just a few seconds of cleaning with a red Scotch-Brite pad. I'm pointing at a spot I just cleaned...

Dave WB4IUY

www.WB4IUY.net

Yaesu FT-101EE Overhaul...

Here's a few pics and info on a Yaesu FT-101EE I overhauled for a friend. These are GREAT rigs, I've owned and rebuilt several over the years. Beautiful RX audio, stable VFO, great TX audio. Lots of tricks and mods for them, not to mention the cool looks of this venerable rig. 

I like to start off with a working radio, if even working poorly. If it's not working, repair it to a point where it is before getting too deep in the restoration. Typically I start by cleaning all of the card connections, rotary controls & switches, and air variable cap rotor wipers with Deoxit D5. Spray and clean all wafers of the band switch assembly. Next, I replace all of the electrolytic caps throughout the rig with new units, I think around 65 pieces. After rebuilding each board, I reinstall it in the radio and power up for a quick test. Replace all power resistors in the PA cathode and grid circuits. Install the driver coupling cap mod. Test and replace driver / PA tubes as needed. Using a service manual, install all documented mods and updates. Perform a full alignment on the RX & TX. Replace all indicator lamps. When finished, these radios will give a modern day rig a good run for the money, and provide many years of dependable service. Here's a few pics of the process...

On the bench, ready for surgery...

Some of the terminal boards have caps that have to be replaced, and aren't easy to get to...

PA compartment open, new filter caps installed (much smaller than the OEM HV caps!)...

Boards laid out, repopulated with all the new caps...

Some of the caps removed and replaced. Notice how tall the HV caps were. The new HV caps are about 1/4 the size, but have higher capacitance and voltage ratings!

Cleaning the rotary switch wafers...

The gray colored cap in the upper edge of the photo needs replacing...

 

Replacing more caps...

Bags of caps, awaiting installation...

Notice the burned resistors in the PA screen grid circuit...

Replacing more caps...

 Notice the difference in the size of the old caps vs. the new caps...

Replacing the driver coupling cap under the trimmer board...

The old HV caps, awaiting replacement...

Getting alignment...

All completed and on the air!

A quick video after the overhaul...

I always say this...I LOVE these rigs :-) I was working in a 2-way shop in the 70's when these were popular. Being a young kid, I never had the money to actually own one, but I got to operate many on the air and loved them.

Dave WB4IUY
www.WB4IUY.net

My 10 Meter Repeater Featured in Magazine!

Back in 1996, I walked to the mailbox one morning, and found a copy of a Japanese magazine - 29MHZ FM Radiosport. I was a little confused, as it was mostly in Japanese. I thumbed through the magazine, and realized they had a feature, multi-page article on my 10 meter repeater! Wow, was I ever surprised. I contacted the author, then JH7LGJ, and thanked him. 

Thinking back, Japanese stations were heard regularly on the repeater at night. The repeater has been on the air since 1994, and with sunspot cycle 22 being so strong, it seems it was heard in Japan quite often. The repeater transmitter was running about 350 watts carrier, and would often transmit from before sunrise, until well after 11pm local. Here's a few pics of the magazine...

I have since rebuilt the repeater, and made many changes. Here's a coupe of links to the original installations and info about their builds...

More about the repeater layout and construction at:  

https://wb4iuy.blogspot.com/1996/05/wb4iuy-29620-10-meter-repeater.html

Dave WB4IUY
www.WB4IUY.net

Tri-band Repeater Antenna Construction Underway...

I'm in the process of making arrangements to relocate my 147.39+ repeater, 224.80- repeater, and 442.400+ repeater to a top perch on my tower at home. After 30+ years experience with amateur radio repeaters, I decided I do not want a fiberglass antenna on my tower...only a metal DC grounded antenna. I decided to set about to design a triband antenna for tower top installation for these 3 repeaters, with the vertical mast robust enough to support the DC grounded antenna for my 10 meter repeater RX side. 

I've started with a batch of DB Products folded dipoles. These are easily modified for correct operation on 2m, 220, and 440. These will all be fed from a single run of hard line via a 3 band tri-plexer. I've successfully fed the 10m receive antenna, 2 meter repeater, and 440 repeater like this in the past. Here's a few pics of the parts I'm working with. I'll update with more blogs as the project progresses. You can keep up with it by looking in the RH column in the "Jump to Blogs of Specific Topics", and clicking on "Repeater-Antennas". 

The long antenna is a Hy-Gain CLR2 I am repairing / retuning to 29.520 mhz for the 10 meter repeater's receiver.  

 The Hy-Gain CLR2 is a DC grounded 5/8 wl CB antenna, and makes a great 10m antenna.

 

Here's a batch of the folded dipoles from DB Products that I am re-purposing  for this custom build. They typically run around 110 ohms, so I'll be building a phasing & impedance matching  harness for these, once tuned.

Load of parts, ready for cleaning and mods. I actually picked these up years ago and stored them away.

Dave WB4IUY

www.WB4IUY.net

Yaesu FL-2100Z Amplifier in the shack!

I've been playing with a new (to me) toy in the shack, recently. It's the Yaesu FL-2100Z HF amplifier. It's fairly rare, not nearly as easy to find as the FL-2100B. This version was more common in other countries, and has all of the WARC bands on the band switch and tuned inputs for them as well. It uses a pair of Cetron 572B tubes at about 2600VDC. Cetrons are the only 572B tubes that can be operated in a horizontal position, none of the other brands have supports on the grids to keep them from sagging into the plates when operated in this position. This is a sweet little amp, and runs around 500-600 watts output, depending on the band. This one was actually bought to serve as a "guinea pig" for a conversion project to the Russian GI7B tubes, but that's a story for another blog. Here's another pic of it, in operation with my old Yaesu FT-901. I love the looks of this lash-up!

Dave WB4IUY
www.WB4IUY.net