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Thursday, January 4, 2018

Part Two - Getting my Amateur (Ham) license and getting on the air.



Then I started my career in Public Safety. Starting out I was a Dispatcher. So, I used a radio a lot. But, it was push the button on the console or activate the foot switch, no real interaction with turning knobs and dials. However, all the radios have vacuum tubes in them. One of the base radios that worked in the 40MHz range was a five foot tall cabinet. That cabinet generated a lot of heat.

Then I went into the field division and had a little more interaction with the radio. We had a squelch control (now squelch control is mostly programmed into the radio), turn the switch to change frequencies and the switch to choose which repeater that you wanted. The mobile radios at this time were a “hybrid” in that the receiver was all solid state, but the transmitter still had one tube (though not a glass envelope tube) in the final Power Amplifier. The unit fit in the trunk and was large and heavy. Of course, some of the cars still had radios in the trunk that required a dynamo to run. When you keyed the microphone (held PTT switch) the dynamo started, and it sounded like a jet taking off. After the dynamo hit peak, you could transmit.

Then we got fully solid-state radios. Not much smaller in the trunk, the control heads were larger but that was because the siren\Public Address board was part of the control head. We still had a squelch control and the knob to change frequencies and push buttons to choose the repeater that you wanted. These radios still had crystals in them that were “cut” to the proper frequency. The crystals were housed in metal heater containers to make sure that they would work at the proper frequency.

As time went on, I got acquainted with a gentleman that ran the radio repair shop for a large construction company doing work in the area. He had been in law enforcement, and volunteered with the local EMS and volunteer Fire Departments. He was not into Amateur (ham) radio, just commercial and Public Safety. From him I learned a lot about radios. With his guidance I took several radios that had been donated by a federal agency to the local search and rescue organization and replaced the crystals with new ones and retuned them to work in the public safety band area. I learned how repeaters worked, that a frequency split was necessary, that most were activated with a CTCSS tone. That changing or adding a new repeater or changing the CTCSS tone on a repeater meant a lot of work, as all the radios that accessed that repeater had to be modified. I even started my own sideline business of installing radios in Public Safety vehicles. It was not unusual to see an ambulance, police car or fire truck in our carport while I spent days or weeks installing radios. A lot of the installations had to have control heads or at least microphones in the front and back of the vehicle. I learned a lot.

Then a promotion came, and I was assigned to administration. Part of that job was management of the radio system and the fleet. It was about time to change the radio equipment. It was getting a little ancient and though it still worked well it was time to upgrade. So, with all the background and knowledge gathered through all the years of radio interaction, we redesigned the system. We relocated repeater sites, added a few and made the conversion to synthesized radios. No more crystals. We used a computer to change the frequencies. We also added Digital Voice Protection, or scrambling to the system. This was a headache as the code had to be created and then loaded into each radio. But, it worked well.

A change of jobs led me to yet another radio adventure. This time it was to assist in the planning and implementation of a county wide narrow band VHF simulcast system. This system would carry traffic for numerous law enforcement, fire and ems agencies. What a project.

Tuesday, December 12, 2017

Ham Radio - Getting the license - getting on the air - Part One

Back in the mid 60’s, I would listen to my cousin W7ZQR transmitting and receiving on his ham radio every time that we would visit, which was frequently. I was fascinated by him talking across town, across the state or across the world to another ham operator. “W7ZQR, W7 Zebra, Queen, Roses transmitting in the City of Roses.” The knobs and dials and switches were amazing, how would anyone know what to do. I decided then that I wanted to be a ham radio operator. 
But, in the 60’s you had to know Morse code. There was the problem. Cousin W7ZQR provided us with a straight key with a battery and light bulb so that I, along with my brothers could learn. He also taught us how to build a simple wire antenna, using wood insulators, made out of wood from a fruit crate, and connecting it to a crystal radio. The antenna was strung between a tall cedar tree and a large oak tree. It was probably 20 feet off the ground and close to 100 feet long. The feed line was just another piece of insulated (if I remember correctly) wire that went from the cedar tree (which was the closest) to our bedroom. I came through the window and connected to the crystal receiver. The receiver was the basic crystal set with the “pick” that you “probed” the crystal with and the enameled coil wound on what looked like a toilet paper roll, that you moved the copper contact across to change frequencies. With a set of headphones, we tried to tune in the world. I honestly can’t remember if we (or I) ever heard anybody or not.

Fast forward to the early 1970’s and the Citizen Band Radio was becoming the thing to have. By that time we were in Boy Scouts, then Explorer Scouts and eventually a Search and Rescue group. I remembered that we have an uncle who lives in Texas (we lived in the Pacific Northwest) that was into radio stuff. My brother and I wrote him a letter and asked if he had a radio. Imagine our surprise when a wooden box came with a single channel Hallicrafters (think it was) with the “magic eye” tube on the front that when you transmitted came down from the top in a “C” shape and full modulation would give you a full green circle. We began to “build antennas” for this. Course not knowing anything about antennas or antenna theory, we probably blew up the radio and never knew it.
We then got a “mobile” CB radio from someone that we knew. It had a Cinch Jones six pin power plug on the back. We apparently gave our friend the wrong information, so when we put the radio in the car (1963 Corvair), it was wired backwards and we ended up melting a large portion of the wiring harness in the dash of the car.
There were various other radios that came and went, most were not worth much when we got them and certainly not worth anything when they left us.

Monday, July 17, 2017

Electrical Protection/Surge Arrestor



It all started with conversation around the “campfire” with some of our RV group. I happened to notice that one of our group had an Electrical Protection/Surge Arrestor device on the end of his power cord. He stated that he had found some bad power in the past so with his new fifth wheel he did not want to take chances. Another of the group with a relatively new Entegra stated that his had come from the factory with one. The discussion them turned to whether hard wired or portable was better. The ones with portable stated that if it malfunctioned, they just took the unit off and plugged directly into the Park RV outlet. The hard-wired ones stated that they could by-pass theirs. Of course, my wife looked at me and asked, "so which kind do we have?" Well, in the almost 30 years we have had RV’s, we have never had one. It was always on the list, but never got close enough to the top to do anything about it. I did not know which flavor I would want, hard wired or the portable. Needless to say, an electrical protection device/surge arrestor went to the top of the RV to-do list.
So I looked at what was available on the market. The two biggest names are the Progressive Industries EMS RV Surge Protector and the Surge Guard RV Surge Protector. CAMCO also has a Power Defender/RV Voltage Protector, however I found more information on the first two.
After looking at the specifications on the two brands, I choose the Progressive Industries EMS-HW50C. In the literature it specifically lists protection against accidental  240V, and the connections are not exposed.
Next thing was to find the best price. Multiple RV Parts and Accessory stores sell them. I finally settled on Tweety’s RV and Truck Accessories. No shipping charge was a bonus. One thing I will say is that Tweety’s marks everything with their logo. So when you get the unit, you might not realize what it is as the box carries a lot of Tweety’s markings.
 
The installation is pretty straight forward. You connect your power cord to one side and the transfer switch to the other. Easy Peasy, as some would say. But, there are a few things that I found that might make your installation quicker and easier.
First thing, location, location, location. Where are you going to install the unit. It is nine (9) inches long, five (5) inches wide and is four (4) inches deep. It needs to go into the electrical box, close to where your shore power cord enters the Automatic Transfer Switch. It should not hamper the storage of the power cord and it should not be close to water, or anything that might damage it. In my electrical compartment, the shore power cord coils and lays on the bottom of the cabinet. I simple held the box in several locations until I found one that would work.

My electrical cabinet also includes the converter/charger and one of my inverters. In the same cabinet are breakers for various DC related items, the slides and the like. My chosen location was away from these breakers and ended up on a side wall under the inverter. There is some discussion on where the EMS Box should be placed in the electrical system. Should it be on the shore power side of the ATS, or be between the ATS and the load center (breaker box). Putting the EMS Box between the ATS and the load center would protect you from a generator that provided over voltage, or a hot ground situation and the like. I placed mine on the shore power cord side, as the RV pedestal is the most likely candidate for getting “bad” power.
The instructions are pretty self-explanatory. Turn off all electrical power to the motor home, including the generator. You do not want to accidently cut into a wire, or take the cover off the transfer switch if you have any electrical power going through the power cord or into the transfer switch. I then held the EMS box to the side wall where it would “live” and used a spring-loaded center punch to mark the hole locations. I drilled 1/8 inch pilot holes, then used #8 by 5/8 self drilling sheet metal screws to anchor the unit to the side wall.

Instructions suggest disconnecting the power cord from the transfer switch, and cutting a length off of the power cord to make the connection to the EMS box. You could also, if you choose to go this route, simply cut your power cord, allowing enough length to get to the EMS box. No need to disconnect it from the transfer switch, or even needing to take the cover off the transfer switch.
Photos before anything was disconnected.
I disconnected the shore power cord from the shore electrical outlet and from the transfer switch. I did not want to give up three feet of power cord length. Might not seem to be a lot, but it also might be just enough that you would not need an extension cord.
Insides of the Progressive EMS
For the side going to the transfer switch from the EMS Box, I sourced some 6-gauge flexible (welding) cable through Amazon. I used flexible 8-guage for the ground wire. Since the cable came in black and red, I used colored tape on black cable to indicate the neutral (white) and the ground (green) wire. I had red and black sheathed cable for the other two connections. I then made the connections on the outbound side of the EMS box. The outbound red and black cables go through pick up coils. The black cable uses the green coil and the red uses the black coil. There is a small arrow on the face of each coil. That arrow (coil side) must be toward the center of the EMS unit to work properly. Again, I used the clamp on the entry side of the EMS Box to secure the cables. I then routed the other end to the ATS switch and made the connections there.
Outbound (to Transfer Switch) connected

I ran the shore power cord through the wire clamp, then connected the power cord to the inbound side of the EMS box. There is a wire clamp provided for each end of the EMS box. I used the existing strain relief clamp on the shore power cable, just relocated it to a different spot. 
Inbound and Outbound connected
Again, these are straightforward, but I always take pictures before I disconnect anything so I have some idea how it should go back together. 
Inbound connection (from Progressive EMS) in center.
 The cables were tied together with plastic wire ties and then anchored to the side panel of the electrical compartment.
Inside the EMS Box there is a jumper that sets the duration from the time the EMS Box is energized to the time it makes the connection and starts providing power. Factory default is 15 seconds. I removed the jumper making it 136 seconds (about 2.25 minutes). This timer is to allow for the HVAC compressor to reset before power is sent to the coach. If you use this long timer, it can be somewhat disconcerting when you plug in the power, see the voltages on the two “hot” legs of the circuit, but you are not getting power to the motor home. Just wait. 2.25 minutes seems like a long time when you are waiting for something to happen, then CLUNK, you will hear the EMS Box make the connection to the transfer switch and you have power inside the motor home.
I mounted the monitor unit next to the EMS Box. There is a lot of cable and I may, at a later time put this monitor inside the motor home. Or, as some suggested I might get a second monitor and splitter and put one inside the motor home and leave one where it is at. The monitor allows you to see immediately the electrical quality when you plug the shore power cord in to the pedestal. The remote also has a switch allowing you to by-pass the EMS Box in the event of a failure. The other nice thing about this EMS Box is that everything inside is modular, so if it fails, the manufacturer will simply send you a new board to replace the one that failed.
Monitor/Switch to the left
One piece of advice – find where you want to mount the EMS Box, drill the holes, screw it in place, check your clearances, then remove the box and make the connections. It would have been far easier to make the connections looking down on the inside of the EMS Box then trying to crawl part-way into the cabinet and make the connections with the box on the side wall.
There are several tutorials on the web on the installation of an Electrical Protection/Surge Arrestor device. Motorhome Magazine recently had an article on these devices. Just about any RV Forum will have multiple entries on it, and the folks at Wheeling It have both a blog post and a YouTube view on it. A link to their site is below.
So the “campfire” discussion lead to the installation of a electrical Protection/surge arrestor device. Just one more thing off the list. I’ll be moving to the next item shortly.