The antenna has been built, here's some addtional information.

I started with the original 154" length using 51" +/- of 1" copper pipe topped with the 102" (actually 102.75") whip.

The antenna was made with an N-connector at the base, as that was what I had on hand. Before running the feedline to my shack, I attached a temporary line in the form of 15' of 0.5" heliax.

I dragged my TS-480 and 12V supply outside and set them up on a Black & Decker Workmate at the base of the antenna.

I was able to load the antenna on 17m, but the SWR without the built-in tuner was >3:1. It worked better on 15m, somewhere around 2.5:1.

With this in mind, I added a 1"-to-3/4"coupling and an additional 20" of 3/4" pipe. Total length now ~176"

This lowered the SWR to < 1.3:1 on 17m, and I can still load it on 15m with the tuner, as well as the lower part of 6m on its own!

Heard some activity on 17m, and my first contact was a VP5 station in Turks and Caicos Is., running about 50W.

The EZNEC model ended up being darned close -- I'm impressed.

Charles
KE5AVC

I have been playing with the demo version of EZNEC 4.0 to model a 17m vertical that I plan to build.

If the model is built with a single element of uniform diameter, the resulting length for resonance at 18.139 MHz is around 156", close to that obtained with the standard 234/f formula for a quarter-wavelength in feet.

The actual antenna will consist of a 1" diameter copper pipe topped with a 102" whip (0.125" dia.), and I have already worked out the mechanical details of this arrangement.

When this configuration is modelled, the length for resonance at the same frequency is some 20" longer or around 175".

This result seems out of line, and I wonder if is expected when using different diameter sections for the radiator.

Looking for some comments before cutting any pipe.

Charles
KE5AVC

Checked the web site -- an impressive set up, but kind of outclasses my manually-tuned Icom IC-820 (running from a battery) into a hand-held yagi.

Maybe I'll have a chance to try it out, as I will be in Toronto over Xmas.

Now if we could get some folks to find another frequency to discuss the finer points of frozen cow patties we could all make a few more contacts!

73
Charles
KE5AVC

You might try searching or posting to the Kenwood group (TS-520_820_530_830) at http://groups.yahoo.com.

The moderator is Bill - K0ZL who is one of the most knowlegdable folks around when it comes to Kenwood repairs.

I seem to recall a post related to the tuning capacitor rotor contact that might the culprit.

Charles
KE5AVC

Sorry - can't spell LINKED.
CK

I worked a pass of AO-51 at 15:57 UT on 11/28 and heard some VE/VA3 stations in Toronto that apparently did not know that they were transmitting to the bird via their repeater.

These guys were having a good old 2m ragchew, until one of them said "I guess some other stations would like to use the satellite" and cleared.

Wondering if anyone else heard this activity and/or has any comments.

Their strong signal on the uplink seemed to play havoc with the majority of others that were looking to make a quick contact.

Is this type of operation legit?

Charles
KE5AVC
EM12

I have successfully worked a few stations on AO-51 with my neighbor using a pair of HTs and an Arrow antenna -- very cool!
I own an Icom 820, and was doing some experimenting over the weekend. After making up the appropriate cables for the antenna, I dragged the 820 outside and connected it to a 12V GelCell battery. The radio, battery, headphones and a digital voice recorder were all set up on "workmate" in my back yard.
I have the radio set for "Satellite-Normal" mode so the RX and TX VFOs can be tuned at the same time. This causes both frequencies to tune in the same direction.
Is this the appropriate way to operate this rig?
There is also a "Satellite-Reverse" mode but I assume this would be used for linear transponder operation.
I was able to make a contact, but due to the fairly wide bandwith in FM mode, I'm not sure that I am tuning the TX appropriately with this setup.
Using the HTs, I found that the uplink frequency did not have to be changed too much over the course of a pass.
Thanks and 73,
Charles
KE5AVC (satellite newbie)

Last Friday 11/04, I was working on a Tokyo Hy-Power HT-106 rig that I had recently purchased from an online ad. This is an older 6m single-bander that does USB and CW with a modest 10W output. The rig is in great condition, but was slightly off frequency and required a bit of tweaking. That night I did an on-the-air check with my neighbor using his 706Mk-IIG and confirmed that I was back in business.

On Saturday morning, I had the rig on, connected to a horizontal loop mounted just above roof level, and was monitoring 50.125. Within 30 minutes I heard a local station talking to a fellow in NC. I followed the QSO up to 50.140 and decided to call the NC station. Got a 5/9 report from him and talked to 3 other stations in the area, one of which replied to me at S9+20dB.

I attribute most of this to sheer luck, however, it shows that even a modest set up can often take advantage of more sophisticated equipment that others are using to the beneift of both.

Charles
KE5AVC
EM12


 

WA9SVD -- I believe you have "unraveled" the mystery of the coiled cord.

Charles
KE5AVC

A filter is an active or passive electronic device that behaves differently at different frequencies.

In the case of a receiver IF filter, which is what your post is referring to, you are dealing with a bandpass filter. This implies that the filter will pass a range of frequencies (a "band"), while rejecting those above and below the passband.

A typical SSB filter is designed to pass a range of  signals somewhere in the neighborhood of 2kHz wide -- say 300Hz to 2.1kHz.

The passband of your receive filter determines how closely spaced signals from different stations can be in the band while allowing you to tune one in and reject the others, and is a primary control of receiver selectivity.

Most vintage rigs like the 520-SE (I have a 520 myself)came equipped with an SSB filter as standard equipment.

Other filters with different (usually narrower) bandwidths were available as options.

I believe that the factory CW filter for your rig was one of 500Hz bandwidth.

Since a CW signal inherently occupies less space in the band than an SSB phone signal, using a narrower filter allows you to still receive the desired signal, while suppressing those nearby.

To answer your question, yes, a CW filter will improve your rig for receiving CW when the bands are busy.

The actual CW filter is enclosed in a small metal "can" and mounts to a spot reserved for it on the IF board close to the existing SSB filter.

I believe that there is a small wiring change that needs to be made when installing it.

There should be no problem locating a source for either the "stock" or any number of aftermarket filters for your rig by searching the Internet.

I believe that the original is quite highly regarded and commands a fair price, so look around.

Charles
KE5AVC

I see that the Science Workshop web site is still on line, although I haven't received a reply to my inquiry regarding the current availability of their kits.
Does anyone know if they are still in business?

Thanks,
Charles
KE5AVC

Wondering if anyone has a readable schematic for a Tokyo Hy-Power HT-106 6m radio.

I recently purchased this rig, and it needs some work.

It came with a copy of the owner's manual, including a microscopic schematic. Using a magnifier, I can make out the diagram, but the component designations are basically unreadable. Also, the schematic is split into several sections, making tracing the lines a challenge to say the least.

Hoping that someone might have a service manual or more legible diagram.

Charles
KE5AVC

I have a T90A as well, but haven't taken it apart as of yet!

Apparently the service manual is available on the mods-dk site as a zip file.

Select Icom from the list on the left, and  then "Manuals" button at upper right.

Charles
KE5AVC

I was looking around various web sites in search of a real heavy-duty soldering iron for just this purpose.

In addition to the regular electronics tool sources mentioned, check sites that sell stained glass supplies, or search some of the internet auctions for this equipment.

These folks have a need for a substantial iron to solder the lead joints in their projects.

I ended up buying a 300W unit for around $15 which does a great job on sheet metal, copper-pipe antennas and automotive wiring. Connectors are a breeze.

150W should be fine for connectors only.

The only down side -- takes about an hour to cool down after unplugging!

KE5AVC

Thanks to KB1LKR for the tip on the counterpoise.

I am active in my local RACES organization, and volunteered for a recent "siren test". This is a monthly activation of the hazard warning sirens that are used to alert the public in the event of a tornado or other similar occurrence.

Anyhow, I was assigned to a siren in a neigboring community that is a good 20 miles from the 2m repeater used by our net control operator to coordinate the tests.

The standard rubber duck that came with my Icom T90A doesn't do that great a job hitting the repeater from in town. I had recently replaced it with a flexible 1/4 wave Maldol whip, but I was still dubious as to whether I would be heard at all from my assigned location.

I had happened on this article previously, and constructed a 19" counterpoise from some very thin  flexible "spring" type wire that I had laying around.

This wire was soldered to a crimp-on terminal that was enlarged to pass over the SMA connector on my HT and bent downwards to form the "second half" of a 1/4 wave dipole. Screwing down the whip holds the counterpoise in place.

This set up worked great, and I easily made it into the repeater with 5W and completed my site report.

A great tip that costs next to nothing!

Charles
KE5AVC