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W3TDH last won the day on June 14

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  1. Jameson W3ESX First let me introduce myself and provide a little of my background. I'm retired out of over 45 years in the electrical craft. I spent a part of my career installing communications shelters from Tierra Del Fuego up to Alaska and from French Frigate Shoals to Tucson Arizona area. The number of shelters I managed the installation of is over 100. The most important part of the installations was usually the Grounding Electrode System. Many of the shelters which I oversaw were self contained and self powered. Since that doesn't bear on your project I'll leave it there. A Ground Rod is a Grounding Electrode. Three Driven Rod Electrodes spaced 2X their length apart, bonded to each other, and then connected to a Ground Busbar or cable entry bulkhead is a Grounding Electrode System. This leads to several questions. Were is your Electrical Meter and Service Equipment in Relation to the Antenna entry? Is it on the end of the house shown in the diagram or is it on the other end. Is there any particular reason that you want to use a steel enclosure for your lightning arresters? Will any other wire of any description enter your home through your grounding bulkhead. (That is the conductive metal panel of grounding busbar were you will be mounting your arresters.) I ask these question because the answers have a large effect on the effectiveness of your grounding system. -- Tom Horne W3TDH
  2. Jim K3MRI Yes that is exactly what I had in mind. It avoids the bad reactions that deploying into the operational area engender and yet makes those who do so the nearest resource of it's kind. The objective in preparing to do this would be in assembling a team with a truly diverse set of skills to provide the widest range of capabilities. Each offered service would have to have two fully qualified lead operators. One or both of them would have to cross train the remainder of the team in how to support the deployment of that resource to the affected area as needed. Emergency Management is now talking about fuel for generators and operating grocery stores as community lifelines. One example of a very supportive deliverable would be to provide basic connectivity so that electronic payment could be available for buying such necessities. An inexpensive long range wireless connection out of the quieted area would be one way to be a lot of help. We connect the EOC 1st, Hospital 2nd, Grocery 3rd, bank branch 4th, and then connect one or more otherwise operational fuel stations... I don't know how to find my way around in an IP stack nor program a IP network. But I can take a laptop, network transceivers, antennas, and support to some effective point. I could install the transceiver antenna support. You have to be able to keep the antennas aimed without attendance. And then aim the antennas at the other points to be served, and adjust them until the software likes the signal. I could do that to as many points of use as were wanted by the officials in situ without messing with any ARES or other services engaged in direct radio support. I cannot imagine a hospital not wanting to have at least basic email service restored nor an EOC for that matter. And if what is needed is to install some basic alarm transmission path between the fire alarm dispatch office and fire stations those same techniques would work there as well. We would certainly need 2 or more operators who could program and control the network but those of us who had cross trained on the node installation tasks would be real force multipliers to that effort. That is just one example. Imagine how welcome a transportable repeater and a mast to get it's antenna 50 feet above whatever it was sitting on might be. We would need to be able to set that mast up on different types of surfaces even if that involved a star drill and a 5 pound drilling hammer. [Side Note: "So John Henry say to the shaker. Now shaker you better pray. Cause I'm swinging 20 pounds from my hips on down, if I miss twill be your burying day! If I miss twill be your burying day!" The shaker pulled a wooden toggle handle on the end of a leather thong wrapped around the drill bit so it would turn and shook the bit between blows to bring the chips out of the hole. the shaker often worked crouching in the face of the tunnel with the driller back far enough to get a good swing. They drilled holes were the blasters needed them and when the fuse was lit the blaster would shout "Fire in the hole!"] -- Tom Horne W3TDH
  3. I think that there is a workable approach that I haven't seen written about. Instead of deploying stage a close by as you can without entering the area that does not have communications services. Set up to support the in situ Ops and listen for the establishment of a resources net or it's equivalent. Then inform them that you have brought that 120 foot of replacement tower they're lamenting the loss of with you. You have several 40 foot tilt ups with dual band J-Poles and the accessories to make them really versatile. [So & So say's he needs relief.] You have a 2 person team who could be en route in half an hour and on location in; give totally honest number. They won't have expected you but if you show up with a broad set of skills and a willingness to TAKE direction rather than give it It could be a good thing. Somehow you have to avoid bringing trouble; meaning "That Guy." The one that always knows a better way and has absolutely no humility about telling the in situ leadership that their DOING IT WRONG;! You also need to bring some real support equipment that you are willing to set up and let others use. None of this "We're the pros from Dover. Just get out of our way" BS! One that that can be provided with a modest investment is 5G long range linking and mesh net support. The 5G links can not be Amateur Radio! Hospitals and EOCs need encryption and Amateur Radio cannot give it to them. Long haul wireless internet can make a lot of friends very quickly. Being very judicious about who gets what kind of on ramp to that Freeway is critical. The first Bozo that goes looking for his daily dose of "those" videos can down your system by taking up all of the effective bandwidth. Those who train would do that kind of support would have to be willing to learn enough to cancel that idiot's access in jig time. There are programs that can be deployed that provide browser based email on a text in and text out basis. Anyone who needs something else has to call a control point RADO and get someone on the incident management team to agree that they need it. No One needs that artistic border that makes their email look like binder paper and turns their entire message into a bandwidth hog. -- Tom Horne W3TDH The hands that hold the nozzle fit a shovel handle to. Get live patients to adequate care. Put the wet stuff on the red stuff. It isn't that hard. "It is dangerous on the face of it, tackling a burning building. The risks are plain…consequently, when a man becomes a fireman, his act of bravery has already been accomplished. Everything else is his daily duty." Edward F Croker, Chief Engineer Commanding, Fire Department of the City of New York. Circa 1910.
  4. Not so fast! The genesis of our hobby is the International Telegraph Code as initially devised by Friedrich Clemens Gerke for use on the German railways. Telegraphy is the first electronic communication. Beginning with Wheatstone's needle telegraph. Followed by Morse's single wire telegraph using Alfred Vail's code which he devised for the Morse Printing Telegraph Company. This became known as the Morse Code which Morse himself had no part in devising but took credit for anyway. -- Tom Horne
  5. The Pup Generator Runs again. If you have wanted to have an inverter generator but cannot afford to buy one of the good Commercial Off The Shelf (COTS) offerings you may want to consider Home Brewing one. I have no interest of any kind in any materials vendor which I mention in this posting. I suppose that most Hams who are thinking about an Inverter Generator realize that the most expensive part of one is the Inverter. It is possible to find one that is not going to put an unbearable hole in your back account balance. Vehicle Salvage yards can be a great source of parts for your project. Many Service Vehicles are fitted with Inverters of various capacities to run power tools at job sites or on board the service vehicle itself. Service Vehicles also get involved in collisions, some of which result in a total loss. Focus your searching on salvage yards that specialize in service vehicles or in trucks and vans. Watch Craig’s List, Freecycle Network, Nextdoor free items lists and other such sources for the small engine you need. You may also be able to get an alternator from such sources. Free Lawnmowers are a great source of 4-7 HP engines. The distinct sub assemblies which will be needed to build your less expensive inverter generator will be: Mounting frame including; Protective carry frame Mounting plate Drive enclosure Vehicle alternator with 150 amperes or greater capacity Universal cooling fan for alternator, Alternator will be turning in the opposite direction from that for which the OEM cooling fan was designed, Drive engine of 5 brake horsepower rating or higher Drive assembly consisting of; Flywheel pulley mounted on engine drive shaft, industrial A pattern, match shaft size, Drive pulley mounted on Alternator drive shaft, industrial A pattern, match shaft size, Drive belt, 36 inch, industrial A pattern, Wiring harness and output connector for alternator, Pure Sign-wave Inverter, capacity appropriate to the amount of DC current available or to your budget. Using modified sign-wave output inverters will cause improper operation of some loads which can then damage the equipment which they supply or are a part of. Some loads can be directly damaged or destroyed by a modified sign-wave supply. The first thing that you will make or buy for this is a mounting plate. If the plate were only for mounting it would be easier to fabricate but since it also serves as the adjusting bracket for the drive belt tension it is probably the most work of the whole effort. If you are not up for cutting the mounting slots in the plate it can be obtained; along with many of the other parts, from the https://theepicenter.com/emergency-power/homemade-generators/vertical-belt-drive.html. Second is the frame on which the mounting plate will be fastened. U Channel Construction strut is a good choice of material because many of the fittings can be purchased at a home center or Electrical Supply House. Enclosure materials can be perforated metal sheeting, Expanded Mesh, and 1/8 inch opening Hardware cloth. I favor the hardware cloth because of it’s lower cost and lighter weight. Use angle metal to cover the edges. The remaining steps of the assembly process are: Fit the universal cooling fan and the small RPM multiplier pulley to the alternator shaft, The OEM cooling fan will not be effective because the alternator will be turning in the opposite direction than the OEM fan was designed for. Fit the larger flywheel pulley on the engine shaft, Mount the mounting plate on the frame, Mount the alternator and the engine on the mounting plate, Adjust the positions of the engine and alternator to tension the A pattern industrial drive belt, Adjust the pulley mounting on the shafts to align them at the same distance from the mounting plate, Make that distance as close as practical to the bearings of the engine and the alternator to avoid placing avoidable leverage on the shaft. Connect the alternator wiring harness, Mount the alternator power connection, Mount the Inverter to the frame, Connect alternator output to inverter supply terminals, Install enclosure material, Note: If you don’t add an Inverter you will have built a “Pup Generator” That is a “Rectified Output Engine Alternator Set” that will produce copious amounts of DC current. That can be directly connected to the Starting, Lighting, and Ignition (SLI) Battery of a vehicle to supply all of the current that could possibly be needed to run several radio stations in or adjacent to the vehicle.
  6. I raced Tech Dories and Lightnings and enjoyed it a lot but after seeing one near miss with a would be rescuer nearly running down a lightning crew member while going to the more visible capsized boat I went to one of the Engineering professors at Boston University and suggested that it would be a very worthwhile project to have fourth year students design propeller guards for the guard boat's outboard motors. One volunteer was operating an ex Coast Guard Motor Lifeboat and was totally offended that anyone thought he should have propeller guards on his inboard engine driven propellers. I was able to bring him right into line by taking a trip with him to an active Coast Guard Lifeboat station. The first thing I managed to have him see was that the newer Motor Life Boat sitting in the launch cradle on it's marine railway had propeller guards on the boat. While we were there the station was alerted for a child being blown out to see on an air mattress. I don't think I'll ever forget the loud haler calling out "Ready Crew Man your boat! Ready Crew Man your boat!" Five Coast Guardsman pounded past us on the wooden walkway to the head of the marine railway and released the Motor Lifeboat so that gravity would accelerate it into the sea. My companion could see those rather large propellers turning as the Lifeboat went down it's marine railway track. The props had to be at 3/4s of maximum revolutions when that boat went into the water at a fairly high speed in order to maintain post launch control of the boat. He saw those props turning from up close and became an instant convert. He led the way in getting the other guard boat operators to except propeller guards. I believe that propeller guards are a readily available accessory from most outboard boat motor manufacturers now but I don't know if that is true of all brands. A couple of those volunteers did impressive conversions of their larger boats to water jet propulsion with the only impellers inside the hull. Everybody in that lightning club was grateful for the change in attitude. A wonderful side effect of the 2 boats converting to water jet propulsion was that since the owners were members of the Coast Guard Auxiliary the Coast Guard came up with some hose, hand-line nozzles, extension tube applicators with fog heads, and a small monitor nozzle so that they had some firefighting capability. Since the 2 jets on each boat had their own drive engine the helmsman could keep the boat in place with one jet and flow 250 Gallons of water per minute to the fire manifold with the other engine. I was quite impressed and so were the 2 owners who had gone to such effort to convert to water jet propulsion. -- Tom W3TDH
  7. If you were selecting a new radio for use in a transportable station focused on EMCOMM which one would you choose. My personal favorite to date has been the Yaesu FT-857D because it is "DC to Daylight:" that is that it will work any amateur band between 160 Meters and 70 Centimeters with the exception of the 1.25 Meter band. Even though I always used a dual band VHF and UHF mobile rig with it the redundancy seemed valuable to me and I did end up using it for that a couple of times. I found the separable control head useful to reduce operating table clutter. My choice for a transportable table has been a 30" by 30" plastic table with folding legs so I didn't want to have to fit every thing on the desk top. I suppose if I use a rack case instead of the well padded shipping case that might not be an issue. One new consideration is that I would like to be able to do near continuous duty digital modes, such as VERA & PACTOR at 100 watts. I think that will require some sort of medium power amplifier to combine with the radio so that both would be running at ~1/3rd of their nominal maximum output power but don't get too hung up on that. There no longer seems to be any "All Band" transceiver rated 100 watts at near the weight and size of the Yaesu FT-857D. The ICOM 7100 is a little larger and heavier. It cannot be configures as a single unit. The controller cannot be mounted flat on a transportable stations front panel. But so far it is the only comparable I have identified. I have used the ICOM 7100 for hospital nets because it is what the commercial radio installers chose for the hospital's radio station. I'm not allergic to it in any sense so don't think I'm ruling it out. The Yaesu FT-897 has a very similar form factor to the FT-857D but it has no VHF UHF capability and the operating controls do not separate from the RF unit. If I used the FT-897 for the transportable station's HF capability I think I would need to add an amplifier/s for the dual band portable so that it could function as a VHF & UHF base station or mobile radio. I include the possibility of 2 separate amplifiers because if I needed to do a lot of digital with the combination the only dual band amplifier I've found, the Mirage BD-35, cannot produce a mobile unit's full output and certainly not at 100% duty cycle. If I would have to carry 2 amplifiers for the mobile VHF UHF radio and 2 for the VHF UHF portable, in order to have the desirable redundancy, things begin getting a bit too heavy bulky and complex. If I separate the HF radio into one rack case and the Mobile VHF - UHF radio into another it might make it more manageable but it would raise the price of a commercial air ticket by another $50. The combined radio and power kits would already cost $100 per ticket. I think I have a pretty good grasp of the accessory and antenna issues so please confine suggestions to the radio itself. Thanks in advance for any ideas. -- Tom Horne W3TDH
  8. Individual equipment for those just starting in EMCOMM would be my first priority. A couple of other things I would consider would be ~10 to 25 Yaesu FT-60 Portable radios with Byonics Tinytrak modems. If I could get the Byonics All In One as a 2way busy channel detecting APRS tracker I would look into those. They are fairly watertight and self contained. I would want to add an external shrouded, water proof, center off double throw switch to select the 2 profiles. If it were possible an external covered Emergency switch which would take 2 motions of a gloved finger to open the cover and throw the switch would be great. Within the present configuration that would have to be integrated into the double pole switch in some way. A completely covered switch in series with the Emergency pole of the Double pole switch would meet that requirement without requiring an electronic redesign of the transmitter. I've already tested the present model inside the next size smaller pelican case and it does fit. If Byonics could add external connectors for power/charging and Data IO that would be fantastic. Since short Winlink messages can be sent over APRS it would give the individual ARES operator a lot of options.That would be the other reason to have a transceiver in lieu of a transmit only design. For any routine traffic the operator could send a short Winlink message without needing the voice channel to make their report. It might make things less exciting for the Net Control Operators but I don't see that as a bad thing. Just imagine the field operators at any event being able to indicate, without first having to get the net control operators attention, that they had urgent or Emergency traffic for them. No more waiting anxiously for the channel to become available. They trip the appropriate profile and net control calls them. That would provide a much smoother information flow by indicating to net control who should have their attention next. They need an ambulance for a patient who is unresponsive, not breathing, in heat stroke, bleeding out, Femur fracture... They can get the channel immediately. Heat exhaustion etc the other profile would indicate non emergency traffic to ask that they be next in the Net Control Operators' cue. I emphasize that in the absence of Emergency or Priority traffic for Net Control the field operators APRS transceiver would be left with the profile selection switch in the Center Off position -- Tom Horne W3TDH
  9. I'd find the best deal I could on 2400 watt inverter generators and LiFePh4 batteries and provide them to our younger ARES members so as to help them be ready to deploy. I might also include a complete 11' x 11' tan Standard Integrated Command Post System (SICPS) tent from military surplus with a "boot wall." The boot wall would make it possible to attach a weather resistant access to a vehicle over a fairly wide range of types. If I could find one in good condition I'd add a single unit shelter heat and cooling unit. Those include a Generator to power the system. Those would make a good support item for an ARES Mutual Assistance Team (ARES MAT). -- Tom Horne W3TDH
  10. The TS-480HX is what I was saving up for when Kenwood dropped the 480 model line. My concern is that buying a modal that has already been discontinued would mean that service or parts support would be unavailable rather soon. That is why I though that an amplifier with a wider range of drive wattage that would reduce the amplifier output as the drive power was lowered might be a good answer. With the right drive range a 300 Watt amplifier could coast along quite happily at 100 watts output and 100% duty cycle. -- Tom W3TDH
  11. W3TDH

    assateague 2019 - 11

    Did I miss it or did you explain the mode of failure of the operating shelter? Tom W3TDH
  12. Isn't the FTDX101MP that huge contesting rig with the built in panadapter that weighs in at nearly 30#? Not exactly an EMCOMM friendly rig. What I didn't see in your answer is how I reduce the workload on the radio / amplifier combination that you are talking about so that the 2 used together will stand up to modes that cause a near 100% duty cycle. 10 watts output on a Yaesu FT-857 is great but doesn't that leave the amplifier running at full rated power output? That would not be likely to stand up to a very high duty cycle. Does anyone know of an amplifier that takes a wider exciter power range and varies the output power with the exciter power. I want to have both the transceiver and the amplifier running at not more than ~1/3 of their respective maximum power output. I already have the Yaesu FT-857 radio. I think that it's form factor is a very good choice for EMCOMM. My plans include a remote antenna coupler, rather than an antenna tuner niether in the radio nor at the operating location. With me it's nearly a religious tenet that you match the feed to the antenna rather than matching the transmitter to the feed line. The other thing that makes me avoid using antenna tuners which are part of the Transceiver is that the range of Impedance which they can match is much lower than an external tuner or a remote coupler. Repeating I want the combination to be able to run at 1/3 of it's maximum output so that it will better put up with a higher duty cycle that approaches 100%. -- Tom W3TDH
  13. Jim The idea would be to build it into a transportable station. That way one could turn it on whenever the digital output power is needed. I would welcome seeing those stations! Now how would you protect it from a possible outbreak of stupid? I don't want to throw 100 Watts into the Amplifiers input and jail break the magic smoke. As I'm sure you have observed once the magic escapes the device in question has to have it's magic smoke replaced before it will work again. Is there, for instance, an attenuator that can be switched in or out in the pathway to the amplifier that would prevent my frying the input with the transceiver's full 100 watts. That could be connected by an electrically operated antenna switch so that when I turn the amplifier on it transfers the feed line to the attenuator. I go to transmit and, because of the amount of attenuation installed, I see a different output level than I expect. I realize my mistake and correct the transceiver's power out. Then I could switch the power to the antenna switch coil off using a self sealing relay When the control relay is energized by the operation of a momentary switch, which connects the amplifier’s DC power supply to the relay, it would open the control pathway to the antenna switch and close a pathway to the control relay's operating coil so that when I release the momentary switch the relay will hold itself closed. The control relay will remain energized until I manually open it’s coil control current or the operating power to the Amplifier is turned off. Since the control power for the relay and the antenna relay both come from the same power lead; which supplies the amplifier, the antenna switch, and it’s control relay both the control relay and the antenna switch would return to their normal states ready to begin the process again the next time I switch on the amplifier DC supply lead. I’m sorry but I don’t know how to draw a ladder diagram, that illustrates the control pathways through a control circuit, on the computer. I would be running the amplifier at 1/3 it's design maximum for actual operation. and what I would see upon testing would be closer to full output. I realize my mistake, reduce the transceiver outlet to the value I need and after repeating the test I would open the manual momentary switch to drop out the relay and thus drop the antenna switch there by taking the attenuator out of the transmit pathway. -- Tom W3TDH
  14. I was saving up to buy a Kenwood TS-480HX 200 Watt output transceiver for EMCOMM use. I wanted the 200 Watts so that I could get ~60 Watts out at 100% duty cycle such as when sending a lot of information digitally from a disaster recovery operations site. Now that Kenwood has discontinued the TS-480 I need another way to get a similar output. As far as I can tell there is no transceiver currently offered new that has 200 Watts output. Does anyone know of one that makes that wrong? I'm reluctant to consider carrying along an amplifier but that may be the only way to get the output power I want. -- Tom Horne W3TDH
  15. Well great. If I make it through this pandemic alive I'll give you a call. -- Tom W3TDH
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