I enjoy history, perhaps more so than others. My first computer was an Apple IIC, purchased in 1985. It had a single 5 1/2 inch floppy drive, no hard drive, and a wee little monochrome monitor. Basically, it was a glorified word processor until I figured out how to connect it to my Amateur Radio transceiver. Here is a picture of my radio room, circa 1988 on Guam:
Radio Room, KH2R Guam Circa 1988
Finding more things to do with it became a hobby of sorts. After a while, I realized that what I wanted was what we termed an “IBM clone,” what is known as a PC today.
When I came across this blog post; History of Computers, I found it interesting and thought I’d share.
It is a joke circulating in Russia at the moment. Kind of funny when you think about it.
In light of the developing situation in Eastern Europe, it may be wise to retain some of those HF broadcasting (AKA Shortwave) sites. It may be too late for Canada, however, the US government still has a few high-powered HF sites that they may want to hold onto for a while. There are several ways that shortwave broadcasting can be beneficial.
Like all radio broadcasting, quality content is needed to attract listeners. Most of what is available on shortwave are religious or transparent government propaganda. There are exceptions to this, but they are rare. Introduce quality programming, and shortwave listenership will increase.
DRM 30 (Digital Radio Mondial) is still in its experimental phase. It has been demonstrated to work reasonably well on HF. Several digital data formats are successfully being used on HF; HFDL, ALE, STANAG 5066, PACTOR and others. DRM 30 has the advantage that H.264 video can also be transmitted.
The VOA has been experimenting with images transmitted via MFSK, AKA the “VOA Radiogram.”
HF is always susceptible to changing propagation. However, it can be reliable enough, especially when frequency diversity is employed, to overcome these issues when no other method of communication is available.
DRM and MFSK can be decoded using a simple shortwave radio and a computer sound card. A DRM CODEC is required, but those are readily available for download.
Analog shortwave broadcasting using AM is still viable. AM has the advantage of being extremely simple to receive and demodulate. Simple receiver kits can be built and run on 9 volt a battery.
While the Soviet Union had an extensive jamming network, those sites have long since been non-functional. Most countries have discontinued the practice of jamming with the exception of China, North Korea, Cuba, and perhaps some countries in the middle east (the usual suspects).
Sample of DRM reception via shortwave:
If the internet is censored or somehow becomes unavailable in that part of the world, shortwave may be the only method to convey an alternate point of view.
Hopefully, things will settle down and return to at least a civil discourse. However, it never hurts to have a plan.
Remember when “NEXTEL (b-b-b-beep), how business gets done…” Well, not anymore. NEXTEL was purchased by Sprint in 2005 and their product lines were combined. Thus, all of these old NEXTEL sites have become redundant and switched off. This particular site was co-located with one of our FM radio clients, which required a power reduction while the old equipment was removed from the tower. I took the time to grab a few pictures of the process:
Former NEXTEL communications equipment room
All of the equipment was removed from the equipment shelter. This site has been switched off since June 2013 and everything in it is destined for the scrap yard. This equipment worked on the 800 MHz bands, which have been re-purposed for Public Safety and Critical Infrastructure, e.g. government users. These racks and radios look like they were expensive:
NEXTEL equipment racks and radios
Speaking of expensive, this site had over 4,500 feet (1,370 meters) of 1 5/8 inch foam coax, which was cut up and scrapped. At today’s prices, that cost $13.25 per foot.
Scrapped transmission line
The tower was rigged:
Rigging tower to remove antennas
Each of the three panel sector mounts were removed and lowered to the ground.
Dropping cellular panel antennas
The NEXTEL antennas were mounted at the 260-foot (80 meter) level of a 395-foot (120 meter) tower. It took some time to remove all of the antennas and equipment from the tower.
Cellular panel antenna array being removed from a tower
I looked on the Sprint website and could not determine if they still offer a push to talk service option (direct talk). With all of the communications options available today, I do not expect there would be much call for it.
For old times sake, here is an old NEXTEL commercial from many years ago:
That was the title of the email with this photo attached:
Disabled high voltage shorting bar, Collins 820D-2 AM transmitter. Courtesy Pete Partinio
That seems about right.
For many, many reasons, this is a bad thing to do. First of all, the shorting bar is the last point of discharge for the high-voltage power supply. When all else fails, this is designed to route the 3,500-volt plate supply safely to ground. Having a stray 3,500 volts floating around inside a transmitter is never a good idea. Fortunately, it was spotted and removed before anything bad happened.
Secondly, it looks like somebody used a 12 VDC cigarette lighter plug as an insulating device. Wow, did they get lucky. This could have started a fire.
As to exactly why it was there in the first place, I cannot rightly say.
And this is why only properly trained people should be working on transmitters, especially tube-type ones.
