Antenna work set

On Saturday June 17th a work party is scheduled to happen. At that time the current south antenna will be moved to another leg of the tower and will become the north antenna. The current north antenna will come down and will be tested to see what is exactly wrong with it. Also with the antenna move it is planned to replace the hardline with new. A lot will be going on that day. If you would like to help you can give Jeremy KC7VCG a call on the repeater or send him an email kc7vcg@47repeater.com or you may send a note via the webpage. It will take several people on the ground plus those on the tower to accomplish this move.

Tacoma Trail Cruisers Smuggler’s Run

The Tacoma Trail Cruisers will be using the repeater to coordinate and pass rider safety information during their annual Smuggler’s Run in the Capital Forest.  Motorcycle riders use trails within the Capital Forest to reach check-points on the way to the final destination. The Smuggler’s Run is scheduled for July 29th and July 30th during the hours of 8:00 am through 4:00 pm each day.  The repeater will remain open to all licensed users throughout the event.
As always, emergency message traffic from any station at any time has priority.

The Tacoma Trail Cruisers are looking for volunteer FCC licensed Amateur Radio Operators to help officiate the Smugglers Run at trail check-points. Contact Dan Burgess at (253) 318-7162 for more information.


The Capitol Peak Repeater Group supports community activities.  Thank you for your cooperation.

Edward Keim, KB7ED

President, Capitol Peak Repeater Group

4/28/2017 Hill Trip

There was a trip up the hill today to try and trouble shoot the antenna and feedline issues and adjust the audio levels threw out the system.
We found a few different issues with the antennas and feedlines. We corrected and repaired what we could with the time and materials we had on hand but the repeaters board will be discussing the options to correct the problems permanently.
The audio issues brought more problems then expected, as of now EchoLink is off the air and the Evergreen intertie is not accessible from our repeater but the north-south trunk is still working threw our site. Because of the complexity of our system there are numerous adjustments that need to be done to make everything work together. We just ran out of time and will complete the adjustments in the near future.
Sorry for any inconvenience and thank you for your patience.

Jeremy Prine
KC7VCG
Board member of the Capitol Peak Repeater Group

Also the APRS digipeater is back on the hill and working properly on 440.800 MHZ.

Update 4/24/17

 Hello all,
Saturdays trip went well and the list of tasks were completed. I went up to complete installation of the “control receiver” and to analyze all the antennas with more knowledge of the tools I was using.
First I finished the control receiver install.  It took a little bit to get the controller programming correct to know when the receiver was active.  Then after that had some audio issues and adjustment.  With the receiver being adjustable on its audio output the controllers audio input and output adjustable its a little tedious getting things just right.  All is connected and working at this time.  Also removed the Icom mobile radio that Bill had been letting the repeater use and will be returning it to him.
Next was to analyze or “sweep” the antennas. (see pictures here) I went threw all the antennas and did this with a Bird SiteHawk and Anritsu S311D Sitemaster.  They both are very accurate TDR (Time domain reflectometer) that will both show you if and were a antenna is resonate and also how long a feed line is or the DTF (Distance to Fault).  When testing for antenna they sweep a frequency range that you set.  In our case we have VHF and UHF systems and I swept different areas for the different antennas.  In the Pictures you can see on the bottom in the left corner a start frequency and the right corner a stop frequency.   At the top of the picture you will see what kind of test it is (Return loss or Distance to fault).  On the Return loss pictures the vertical scale is what signal level in DB that is not leaving the antenna or is getting reflected back.  The horizontal scale is the frequency.  A feed line and antenna that is in good shape should be at -14 or lower, -14DB is about a 1.5 SWR.  So as you can see we have some issues on some of the antennas.
The DTF pictures are a used to find bad connectors, damage in a feed line and a very precise measurement of a feed line if it is unknown. The test equipment lets you choose what kind of feedline you are using and takes into account the los of the cable on your frequency, velocity factors, ext. On the picture for the “Southlink you can see the line is pretty flat till about 20 feet then there are two bumps, that is the length from the jumper from the cabinets to the polyphaser.  The first bump is the connector and second is the Polyphaser.  The large spike is the antenna and the complete length of the antenna system. Some of the DTF pictures you can see where the main hard lines stop and then go to a short jumper to the antenna by the small bump befor the large spike of the antenna.
The “mainsouth” picture shows a flat line or completely dead antenna system, not a good thing. The northmain there are two pictures that show how the wind was “changing” the resonance of the system, that indicates that there is probably a mechanical problem (bad connector or damaged feed line-antenna).  The “backup repeater” return loss picture shows what a antenna in good condition looks like.   The “V” on the graph is clean, smooth and on frequency.  It is a very precise Ham band antenna and not a broad band commercial type antenna but gives a good idea of what its suppose to look like.
The North, South and Echolink link antennas are Log Periodic Yagi antennas and look different then a Omni vertical because they are designed for a very large band of frequencies.   The Echolink is the best example of what they should look like.  Each dip is the different elements on the yagi and what frequency it is resonate at.
The APRS and Control Receiver antennas are both “open stub jpoles” and both have issues as you can see in the pictures.  They are good antennas and have there uses but really are not built for the conditions on the hill and probably just need to be replaced.
I think I covered it all, if not let me know or if you have questions.
JEREMY PRINE
KC7VCG
SECRETARY/TREASURER
CAPITOL PEAK REPEATER GROUP

Current update status 4/19/2017

On Apr 19, 2017, at 9:00 PM, Jeremy Prine <kc7vcg@47repeater.com> wrote:

I think most everyone knows what has been done on the hill lately but I wanted to give a update of what still needs to be done and some ideas to think about.

We all know there is major testing to do on the antenna system to do that will involve climbing the tower.  David and myself talked about this today and we will probably be scheduling to do this in a month or so when weather hopefully becomes more predictable.  Because of scheduling with Davids family and his wife’s business project we will probably do this work on a weekday as a “community service day”.  We can do the testing side with just us two but more people would be nice.  If a antenna or feed line needs repair or replacement it will be needed to have more people. We will try and give as much notice as possible so everyone knows and can get the day off to attend if they want to take part. There are still a few jumpers needed to be made that go between the polyphasers and the cabinets also.

I also have been learning more about some of the equipment I have access to from work so I will be doing more detailed analysis of the antenna systems so we have a better idea of what we need to do when we climb the tower. I will do this testing this weekend.

We also had a new Control receiver donated to us that is in the cabinet but not hooked up an functional yet.  I will be tackling that this weekend. The current control receiver is a radio Bill let the group use in a pinch when we had the malicious interference a couple years ago, once removed it will be returned to Bill.

Although not a major thing but the weather radio is very old and was modified to give the necessary signal for the controller to activate when a alert is sent by NOAA.  After a little research I have found a few manufacturers that make weather alert radios that have a “Signaling” circuit built into them and audio outputs that will work with the controllers for around $50.  Another nice thing about the newer radios is when the alert is done the signal goes away so the controller does not have to be set to listen to the weather radio for a set amount of time that’s usually longer then the actual alert.  Another small reason I suggest this upgrade is the audio quality will probably be better although after listening and watching the signal from NOAA’s radio station today on a spectrum analyzer it is way over modulating and is most of the crappy audio problem we hear.

There is a couple cables that interconnect different components in the cabinets that honestly just bug me (but work) that are the wrong length or superficially damaged that I don’t like.  I will have to custom build these in time.

Something that is going to take time and patience is numbing or labeling all wires or cables.  This will involve numbering, writing a description of the cable and circuit, fuse value if power wire, and if a audio-control cable the port of controller and pin-out of that cable.  One of the reasons this project was proposed is to clean things up and make it easier to work on.  After all the cables are labeled like this there will be a block diagram and simple schematic put together along with a control operator programming book that can be easily followed and modified as repairs and or upgrades are done in the future.

Like I said I will be going up this weekend on Saturday after breakfast and will do more detailed antenna testing and trying to get the control receiver switched over.  If you want to join me or help let me know. it will probably be a all day trip about 3-5pm before coming down the hill.

Also the APRS and control receiver antennas are both “homemade” open stub jpoles.  There is nothing wrong with these antennas but are not really designed for the conditions they endure on the peak.  If anyone has ideas of what these could be replaced with and or antennas to donate might be something to put on the list down the road.

I’m getting to much gray hair! lol another thing is EchoLink.  We have all the necessary components (Rigblaster that was acquired at the swap meet, internet at the cabinets and computer) to move the EchoLink up the hill.  I need to configure the Rigblaster and bench test it and then move it up the hill.  I did testing a couple weeks ago with internet on the hill and there is no need to do any firewall or port forwarding within the Hamwan system. That was a big relief.  I will try and do this move in a couple weeks.

 

Jeremy Prine    KC7VCG

Board member of the Capitol Peak Repeater Group