February 2017
M T W T F S S
« Jan    
 12345
6789101112
13141516171819
20212223242526
2728  

Archives

Categories

The Energy Onix Pulsar transmitter

Engineering Radio: The Oh Dear God Edition.

I have been tasked with fixing one of these glorious contraptions. Aside from the usual Energy Onix quirks; design changes not reflected in the schematic diagram and a company that no longer exists, it seems to fairly simply machine. Unfortunately, it has spent its life in less than ideal operating conditions.

Energy Onix Pulsar 1000 in the wild. Excuse the potato quality photo

Energy Onix Pulsar 1000 in the wild. Excuse the potato quality photo

Upon arrival, it was dead in the water.  Found copious mouse droppings, dirt and other detritus within and without of the transmitter.  Repaired the broken start/stop switches, fixed the RF drive detector, replaced the power supply capacitors and now at least the unit runs.  The problem now is the power control is unstable.  The unit comes up at full power when it first switched on, then it drops back to 40 watts, then after it warms up more goes to about 400 watts and the audio sounds distorted.  This all points towards some type of thermal issue with one of the power control op amps or other composite device.

After studying the not always accurate schematic diagrams, the source of the problem seems to be carrier level control circuit.  This is based around a Fairchild RC4200AN (U10 on the Audio/PDM driver board) which is an analog multiplier chip.   That chip sets the level of the PDM audio output which is fed into the PDM integrator circuit.  Of course, that chip is no longer manufactured.  I can order one from China on eBay and perhaps that will work out okay.  This all brings to mind the life cycle of solid state components.  One problem with the new technology; most solid state components have a short production life, especially things like multiplier chips.  Transmitters are generally expected to last 15-20 years in primary service.  Thus, transmitter manufactures need to use chips that will not become obsolete (good luck with that), or purchase and maintain a large stock of spare parts.

In the mean time, the chip is on its way from China.  Truth be told, this fellow would be better off with a new transmitter.

The isocoupler and the SX2.5

Second post in the series, “things to do with a truck body tool box.”

We have this client who, several years ago, moved their translator to their AM tower. All is well for a few months, then the much beloved Harris SX2.5 transmitter begins burping.  The SX2.5 transmitter being of an age when, apparently, VSWR fold back circuits were just a gleam in Hilmer Swanson’s eye.  The correct description of the sound made over the air during this event would be “motor boating,” because that is what it sounds like.  Obviously, very undesirable.

Thus, the isocoupler was removed from the tower, dried out, water proofed and replaced.  That lasted about six months.

Once again, the isocoupler was removed from the tower, a capacitor was remounted, drain holes and a small vent added to the top of the unit and it was replaced.  That lasted about a year.

I am getting a little tired of this and so is the client.  Time to rethink the entire set up.

We had several left over parts from various AM decommissionings over the last few years which included these nifty sample loop isolation coils:

AM antenna system sample loop isolation coil

AM antenna system sample loop isolation coil

Why not repurpose one of these to make an isocoupler for the translator?

Enter; the truck body tool box.  This one is slightly smaller than the last one, measuring 23.5 x 18 x 16 inches (60 x 45 x 40.5 cm).

The isolation coil consists of 35 turns of 3/8 coax on an 11.5 inch diameter form.  The coil length is 15 inches.  I calculate the length of the coax on the coil to be out to be right around 100 feet using the π x D x (turns) formula.  I measured the inductance with my analyser, which came out to 200 μH.  Not to shabby.

Checking length of cable with TDR

Checking length of cable with TDR

The coax is Cablewave FCC38-50J which has a velocity factor of .81 and the TDR shows it to be 100 feet also.

Coil impedence and reactance

Simple coil impedance and reactance

At 860 KHz, the isolation coil presents 1,200 impedance.  I don’t think that will be good enough for that cranky old SX2.5.  I decided to make a parallel LC circuit (AKA a tank circuit) to bring up the impedance some.

Tank circuit formula:

tank_circuit

Where:

FR = Resonance frequency in Hertz
L = Inductance in Henrys
C = Capacitance in Farads

Given that I have two left over capacitors, one is a .001 μF and the other is a .0012 μF, those values determine where the coil needs to be tapped.  I also wanted to have a good bit of coil in the circuit on the tower side before the capacitor tap to dampen any lightning strikes on the tower.  Thus the inductance needs to be about 28 μH.

Using Wheeler’s coil inductance formula:

L= (d2 x n2)/(18d+40l)

where:

L = inductance in micro Henrys
d = coil diameter in inches
l = is coil length in inches
n = is number of turns

I removed a small portion of the outer jacket on the coil at approximately the 28 μH point (12 turns) then installed a .0012 μF capacitor.  I used a small variable capacitor to tune for resonance on the carrier frequency.  With this set up, at 860 KHz, there is >47,500 impedance.  That goes down to about 16,000 ohms +/- 10 KHz.

That should make things better.

Then I mounted the coil and capacitor in the truck body tool box.  There is a fair amount of stray capacitance from the box itself, which raised the resonant frequency by 5 KHz.

Device Under Test, initial testing of isocoil after fabrication

Device Under Test;  initial testing of isocoil after fabrication

Resonance is slightly above the carrier frequency with the permanent fixed .0012 μF capacitor.  I think this will change once the unit is connected to the station ground plane.  The network analyzer indicated there is too much capacitance in the circuit.  Unfortunately, this may be as good as it gets, however, the analyzer shows the impedances are still pretty high:

Frequency (KHz) Impedance (Ohms) Deviation from Carrier (KHz)
850 9,950 – 10
855 14,720 – 5
860 28,590 0
865 59,580 + 5
870 24,780 + 10

The base impedance of this tower is 34 ohms on the carrier frequency, so the isocoupler should be invisible to the transmitter across the 20 KHz occupied bandwidth of the station.

The FCC38-50J cable has a loss of 1.04 dB per 100 feet at 100 MHz, which is the figure I will use to calculate the insertion loss on the FM translator antenna system.

The old isocoupler is made with RG-214, but likely a somewhat shorter length.  RG-214 cable has a loss of 1.9 dB per 100 feet at 100 MHz.

Installation:

Isocoil mounted on back of ATU

Isocoil mounted on back of ATU

Isocoil mounted on back of ATU

Isocoil mounted on back of ATU

Before and after measurements with the network analyzer show a very slight change in the reactance at the tower base.  Nothing major and easy enough to tune out with the series output inductor of the ATU.

If I where to do this again, I would simply tap the coil at ten turns from the bottom, measure the inductance and install the proper value capacitor.  Since this had to be constructed with the parts on hand, less the truck body tool box, it because a bit cumbersome to get close to the resonant frequency.

All this got me thinking; there are other possible uses for such a design.  Crossing a base insulator with Ethernet cable always presents some unique problems.  I know the WISP forum that I read, they are always talking about how difficult it is to mount an antenna on an AM tower.  What if… armoured Cat5e or Cat6 cable was used with water proof RJ-45 jacks?  Something like that could carry Ethernet data and DC voltage past the base insulator to a three or four around sectorized access point and an edge switch or router mounted on the tower.

Armoured category cable specifications

Armoured category cable specifications

just thinking…

Anyway, it would not be hard to make coils and install capacitors for the right frequency

Прощаться!

This information is from an occasional reader who wished to remain anonymous.

Another AM station surrenders its license, this time from north of the border. CKSL, London, Ontario, Canada is gone for good.  Current owner, Bell Media, has determined that it would cost more to repair the deficiencies with the antenna system than economically feasible, especially considering it’s low ratings.  Here is their filing with the CRTC:

Bell Media is the licensee of CKSL-AM 1410, assuming stewardship of the station in 2013 as part of the Astral Media acquisition.

A technical review of the transmitter site was recently completed both by Bell Media and contractors, which has resulted in the determination that the AM array poses an unacceptable risk from a health and safety perspective.  The five towers are experiencing serious structural degradation and also require repairs to the aviation safety lighting system. In addition, the building which houses the transmitter has shifted off its foundation (as have several of the individual tower sheds).

Given these problems, Bell Media would need to make a significant financial investment to bring CKSL-AM’s transmitter up to compliance with Human Resources Development Canada, Industry Canada and NavCanada operational codes and standards, all of which is estimated to exceed $3 million dollars.

From a market perspective, CKSL-AM has consistently ranked last out of all ten commercial stations in the London market, both in audience share and revenue generation, over the last several years.  In fact, since 2013 the London market has seen radio revenues drop 4% and CKSL-AM generates the least amount of revenue of the stations in the market. Even with a significant investment in programming, this trend is unlikely to be reversed. 

In light of the significant capital costs coupled with the absence of revenue and audience share, Bell Media is respectfully requesting the revocation of the CKSL licence.

Well, 24/7 comedy will do that to you.  Somebody in the business said to me recently “The listeners are abandoning radio!”  No, it is the broadcast station owners who are abandoning their listeners and their cities of license.  I have a news flash for all current broadcast station owners; as surprising and radical as this might sound, bland, boring, canned, completely irrelevant, dismal, uninformative, unimaginative, unentertaining, dreary, stale, unenjoyable programming will drive away even the most loyal listeners.  People really want to listen to radio, it is an easy habit and readily accessible.  Radios are ubiquitous; they are in our kitchens, bedrooms, cars, hotel rooms, offices, restaurants, barber shops, etc.  That, however, may not always be the case, as more and more people move Spotify, Pandora, or Apple radio when they are tired of the disappointment.  I was listening to a certain sports radio format the other day and I kept waiting for something interesting to happen.  I waited and waited. I would say to myself; okay, this will be the segment when I will learn something or be entertained.  This upcoming guest will say something interesting.  Sadly, those expectations were never met and I will never tune into that station again. Elevator music would have been better.  Worse than sports radio, 24/7 comedy is the absolute death knell.  This is like saying; we are out of ideas and we do not care.

Here are a few pictures of the former CKSL-AM transmitter site:

CKSL antenna array

CKSL antenna array

CKSL_transmitter

CKSL transmitter building

CKSL_transmission

CKSL transmission line bridge

CKSL_tower

CKSL tower base

Actually does not look too bad, at least the field is mowed. I have seen much, much worse.  Those bolt together towers, though. I would bet that they are the real problem, bolts are deteriorating faster than the tower steel. Very likely all the towers need to be replaced and that is why the license is being surrendered.

If you are a radio geek, get out there and take some pictures of your favorite radio station.  If the current trends continue, eventually they will all be gone.

The Horns of a Dilemma

Alternate title: Building and ATU in a truck body tool box.

Alternate title II: I should get paid extra for this shit.

There is an AM radio station that is near death but the owners do not want it to go away.  Nor to they want to spend very much money to keep it around, thus the dilemma.  At the transmitter site, there are a multitude of problems; leaking roof, very old rusty ATU, rotting support posts and transmission line bridge, equipment racks rusting out, nothing is grounded properly, the building is full of junk, snakes and mice have moved in.  To further complicate things, the tower and transmitter building serve as an STL relay point for two of the market’s FM stations.  There is also two translators with antennas on the tower.  The ATU and tower light choke box are rusting through, which is causing arcing and broadband RF noise that is interfering with the FM station’s STL receiver.  There was a home made isocoupler for one of the translators that was allowing AM RF back into the building which was creating havoc with everything.  Because of this, the AM station is currently silent.  In short, it is a mess.

WCHN ATU

WCHN ATU

The red box on the bottom is the ATU, the plywood box on the top with the peeling yellow paint is the home made isocoupler, the tower light choke box is behind the isocoupler.

Crumbling old ATU output capacitor in series with tower

Crumbling old ATU output capacitor in series with tower

This was the capacitor that was feeding the antenna, .0041uf, 10KV 8 amps.

We started remediation on this last February, which is not optimum time for replacing rotting wooden posts.  However, we were able to clean out the building.  The leaking roof has been repaired.  I was able to find a few old racks from a Schafer Automation system to replace the rusted out original racks.  I began the process of grounding the equipment racks, the incoming transmission lines for the STL, etc.

Cool morning, Garter Snakes warming themselves on top of a Moseley DSP-6000

Cool morning, Garter Snakes warming themselves on top of a Moseley DSP-6000

Garter Snake

Garter Snake

We will have to find out how they are getting in, the plug up those holes.

Then there was the ATU and tower light choke enclosures.  Original to the 1952 sign on, they were past their serviceable days.  Since this is all being done on a budget and nobody wants to spend money on an AM station that has little or no listeners and even less revenue, we had a problem.

Then somebody suggested building an ATU in a truck body tool box.  Well…  This isn’t the Meadowlands, so if there are no other alternatives then okay, I guess.  Off to Amazon to order a tool box.  This particular unit seems fine, my only comment is on the gauge aluminum (or aluminium if you prefer), which is slightly thin for holding up all those parts.

ATU built in a truck body tool box

Fabrication shop, ATU built in a truck body tool box

Still, the box itself is nice enough and certainly better than the old one.  I was able to reuse the inductor and the Delta current meter but the old Sangamo capacitors crumbled in my hands when I removed them.  I also saved the feed through bowls, J-plugs and other parts.  I used some copper strap to run a good RF ground from the input to the ground connection.  Overall, I am pretty pleased with the finished product.  It is a little bit tight in there, but this station only runs 1 KW, so it should be fine.

Replacement ATU mounted

Replacement ATU mounted

So, new pressure treated posts installed, the box was mounted and the transmission line connected.

Replacement ATU under power.

Replacement ATU under power.

Reused Schaffer Automation racks, much better than the 1950's Gates racks

Reused Schafer Automation racks, much better than the 1950’s Gates racks

The reused racks are old, but serviceable and a big improvement over the old, rusting out racks.  I was able to bond each rack to the ground strap that used to connect to the RCA BTA-1 transmitter.  There is one more rack to install to the right of these two.  That should give us more than enough rack space for this site.

The station is back on at full power and not interfering with the FM STLs or the translators.  You can actually touch the rack and not get an RF burn!

We are also working on an air conditioner.

Other work at this site; cleaning out the building, replacing the tower light photocell, installing a ground buss bar, some STL lightning protectors, dress the transmission lines, etc.  It is a work in progress.

 

Medium Frequency ATU design

This is a topic I have covered before, but it is worth doing it again for future reference.  The previous post covered downgrading an AM transmission facilities for WGHQ, Kingston, NY.

This is part II of that process.

WGHQ transmitter site, towers 1 and 2 removed

WGHQ transmitter site, towers 1 and 2 removed

The old towers have been cut up and put in a scrap metal dumpster. They are off to China to be melted down and made into a submarine or a missile or a tank or something useful like that.

Towers scrapped

Towers scrapped

The directional array had a three towers in a straight line with a common point impedance of 60 Ohms.  Dropping two towers greatly changed the electrical characteristics of the remaining tower, therefore the existing ATU needed a bit of reworking to match the 50 Ohm transmitter output.

First step, correct a few deficiencies left over from the old array.

Vise grip tower feed

Vise grip tower feed

This vise grip RF connection has to go. The problem is where the tower erectors attempted to solder the copper tubing.  That tower base plate is pretty big and I would wager they didn’t use enough heat to make the solder connection.  They were probably working in the winter time, thus the “temporary” fix.  This tower was put up in 1993, so that temporary fix lasted 23 years.

I removed the offending tool and soldered the connection to another part of the tower with silver solder.  The smaller cross bar made a good connection point.

RF feed correctly connected to the tower

RF feed correctly connected to the tower

After soldering, I cleaned up and sprayed some grey primer on it to prevent rust forming where I scraped the paint off.

Next, I made an impedance measurement:

WGHQ tower base impedance measurement

WGHQ 920 KHz tower base impedance measurement

That junk on the upper part of the graph is coming from WHVW on 950 KHz. The tower itself looks pretty good, 77.6 Ohms resistance with 130 Ohms inductive reactance.  Since this is not a part of a directional antenna system, the ATU design is pretty straight forward.  Given that WHVW on 950 KHz is located 10.41 miles away, a low pass filter design is optimum.  A basic low pass filter T network has inductive input and output legs with a capacitive shunt leg to ground.

T network diagram

T network diagram

Each leg is used to match the 50 Ohm transmission line impedance (R1) to the 77.6 Ohm tower impedance (R2) and cancel out the 130 Ohms of inductive reactance.  This is a vector impedance problem, much like a vector force problem in physics.   Some basic arithmetic is required (always include the units):

X1, X2, X3 = √(Zin x Zout)

X1, X2, X3 = √(50Ω x 77.6Ω) or X = 62.28Ω

The value of inductance or capacitance for each leg is calculated using the basic inductance or capacitance formulas:

L (μH) = XL / 2πf(MHz)

And

C (μF) = 1 / 2πf(MHz) XC

Thus the input leg, or X1 = 62.28Ω / (6.28 x 0.92 MHz) or 10.78 μH

The Shunt leg, or X2 = 1 / (6.28 x 0.92 MHz x 62.28Ω) or .0028 μF

The output leg is a little different.  The tower has 130 Ohms of inductive reactance that needs to be cancelled out with a capacitor.  Rather than cancel out all of the inductive reactance, then add an inductive output leg, the tower reactance can be used as part of the tuning circuit.  The design calls for 62.28 Ohms inductive reactance, so 130Ω – 62.28Ω = 67.27Ω, which is the value needed to be cancelled by a capacitor:

Output leg, or X3 = 1 / (6.28 x 0.92 MHz x 67.27Ω) or .0025 μF

A little Ohm’s law is used to calculate the base current for both the day and night time operations.

Ohm's law pie chart calculator

Ohm’s law pie chart calculator

Thus the daytime base current is I = √(P/R) or I = √(1000 W/77.6Ω) or 3.58 Amps.

Night time base current is I = √(38 W/77.6Ω) or 0.70 Amps

Current handling requirements:

Base current is calculated to be 3.6 Amps at 1,000 Watts carrier power.  Allowing for 125% peak positive modulation makes it 5.7 Amps.  Having safety factor of two or 11.4 Amps output leg and 14 Amps input leg.

Voltages: 353 maximum input voltage, 439 output.

Thus, 20 amp, 10 KV parts should work well.

The designed schematic for the ATU:

WGHQ ATU Schematic diagram

WGHQ ATU Schematic diagram

Putting it all together.

Since the tower looks fairly broad at 920 KHz, we are going to attempt a nice broadband ATU to match it.  This station is currently programmed with a classic country format, and I have to tell you; those old Conway Twitty, Merle Haggard, Patsy Cline, et al., songs sound pretty good on the old AM radio.  The Subaru stock radio has HD, which also has a nice broad IF section, thus allowing all those lovely mid-high range frequencies through.

This is the existing ATU, which I believe was built by Collins in 1960:

WGHQ Tower 3 ATU

Existing WGHQ T network ATU

The ATU building is a little rough, but the ATU itself is in remarkable shape for being 56 years old.  The input leg inductor is in the center and will be reused as is. The large Jennings vacuum capacitor at the bottom is a part of the shut leg.  Its value is 2000 pF at 15 KV.  The top vacuum capacitor is series output cap, its value is 1000 pF at 15 KV.  The basic plan is to move the upper cap down in parallel with the bottom cap.  The shut leg inductor will be kept in place to tune out any access capacity.  For the output leg, I have a 2500 pF mica cap and a 10-100 pF variable cap connected in parallel.  The inductor on the output leg will be removed.

After some re-work on the ATU components, I tuned everything up.  The easiest way to do this is to disconnect the legs, measure them individually and adjust them for the desired reactance, which in this case is 62.28 ohms or thereabouts.  The output leg was measured with the tower connected since the tower reactance is a part of the tuning circuit.  The input leg was right about 10 μH.  The shunt leg turned out to be about 0.002 μF.  This is often the case, theoretical values are slightly different than field values due to stray capacitance and inductance in the connecting straps, etc.

This is the load, as measured at the output terminals on the transmitter:

WGHQ tower load as measured at the transmitter output terminals

WGHQ tower load as measured at the transmitter output terminals

Slightly asymmetric on 910 KHz, but overall pretty good. There is a fair amount of phase rotation in the transmission line due to the length from transmitter to tower (855 feet, 260.6 meter), which works out to be 0.93 wave length allowing for the 86% velocity factor of the transmission line.

Time to pack up and go home.

Downgrading an AM radio station

WGHQ in Kingston, NY has been downgraded from a 5KW DA-1 to a 1KW non-DA system.  This was done because two of the three towers in the directional antenna array dated from 1960, were in very rough condition and needed to be replaced.  The remaining tower (furthest from the transmitter building) had been replaced in 1994, is in good condition and is being kept as the non-directional radiator.

Here are a few pictures:

WGHQ 3 tower directional antenna array, Port Ewen, NY

WGHQ 3 tower directional antenna array, Port Ewen, NY

More deferred maintenance

More deferred maintenance

RF and tower light feed disconnected from tower base

RF and tower light feed disconnected from tower base

Second tower base vegetation not as bad, tower disconnected

Second tower base vegetation not as bad, tower disconnected

WGHQ transmitter and original Collins phasing cabinet

WGHQ transmitter and original Collins phasing cabinet

First tower video (sorry, I appear to have no idea what I am doing with the camera):

Second tower video, this one is better:

Towers on the ground:

I made measurements on the third tower and constructed a temporary ATU with parts on hand to get the station back on the air. They are now running 1 KW day, 38 watts night, as per their CP. I will be going back up to finish the job once the brush has been removed from around the existing tower and the ATU building has been repaired.  The coverage with 1 KW is not bad, actually:

Predicted coverage map from FCC website

Predicted coverage map from FCC website

The translator is on its way.

The inglorious task of AM antenna array maintenance

AM radio stations are rough customers. They frequently operate on the margins, both in terms of ratings and revenue. Their transmitter plants are complex and very often have been on a reduced maintenance schedule for years, sometimes decades.  Those of us that understand the operation of AM transmitter plants and all their quirky behaviours are getting older.  I myself, feel less inclined to drop everything and run off to the AM transmitter site when things go awry.  Seldom are such efforts rewarded, much less acknowledged.  Station owners are also finding that their previous demands are unrealistic.  For example, time was that any work that takes the station off the air had to be done after midnight.  These days, I can tell you, I will not be working at your radio station after midnight.  You can find somebody else to do that work.

Thus, today, we took this particular AM station off the air from Noon until 3 pm to diagnose and repair a problem with the four tower daytime array.  Once again, this involved a shift in common point impedance and a drastic change in one tower’s current ratios.

Antenna Tuning Unit, mice have made a mess

Antenna Tuning Unit, mice have made a mess

In all fairness to the current owner, this ATU reflects years of neglect. At some point, mice made a home in here and created a mess. The ATU smells of mouse shit, piss and mothballs.  It is full of mouse droppings, grass seeds and fur.  All of the ATUs in this array are in similar condition.

Paper wasp, inside ATU

Paper wasp, inside ATU

It was warm enough that the wasps were active, if not a little bit lethargic.

Broken stand off insulators in ATU

Broken stand off insulators in ATU

This coil is being held up by the tubing that connects it to other components. When the ATU was built, no nylon or cork bushings were used between the insulators and the wall of the ATU they were mounted on. Heat cycling eventually did all of the insulators in.

Catwalk to the other towers

Catwalk to the other towers

Catwalks to the other towers. At least the swamp grass has been cut this year, it is only four feet tall instead of ten.

Tower base

Tower base

The tower bases are all elevated above the theoretical maximum water level. The ATUs are also up on stands with platforms build for maintenance access.

ATU Work "platform"

ATU Work “platform”

I cannot even blame the current owner, who has spend considerable money to make repairs and upgrades to this site. It is very difficult and very expensive to catch up with deferred maintenance. Sadly, most AM stations we encounter have similar or worse problems.

I think it is too late to save many of these AM stations.  The technical issues, lack of revenue, perceived poor quality, lack of good programming are all taking their toll.  At this point, the hole is so deep there is no hope of ever getting out.  The FCC’s faux interest in “revitalization” followed by two years of stony indifference seems to be a final, cruel joke.

The old school marketing campaign

I found these old drawings in the filing cabinet and thought they were kind of cool. They look like they were drawn sometime in the 50’s for the WPTR studio at 1860 Central Avenue in the Town of Colonie.

WPTR-billboard

It looks like there was a lot of Neon, including a speller, which I take to mean the sign would spell “W-P-T-R 1540” then turn off again.

This was the sign for the entrance to the studio building

WPTR sign for front of old studio building at 1860 Central Avenue

WPTR sign for front of old studio building at 1860 Central Avenue

I think this is a take off on the old KHJ sign in Los Angeles.

Something fun

So, I spent wasted several hours on this SDR website over the holiday weekend:

University of Twente SDR website

University of Twente SDR website

This is a web based SDR hosted by the University of Twente in Enschede, Netherlands. I enjoyed listening to the European medium wave and shortwave stations available.  Something that is always fun to checkout: UVB-76 on 4625 KHz.

Have fun!

PS: A special thanks to all those who have donated to the cause via the donate button on the upper right side bar.  I had enough money to buy a FUNcube dongle SDR.  I think I have all the other necessary hardware to launch one of these sites myself.  If or when that happens, I will post a link here.

Accidents, mistakes, mishaps and other tales

Lets get started:

Results of a deer vs automobile accident

Results of a deer vs automobile accident

It does not look like much, however, that is about $5,500.00 worth of damage. What you don’t see is the mashed oil cooler and radiator. This happened on my way from one place to another during the early morning hours. I was traveling at about 55 MPH when a deer bolted from the woods and entered the roadway from the right. I did not have time to break.

In a ditch

In a ditch

A momentary lapse of attention causes loss of $80.00. I think I was adjusting the defroster as I was driving down the road when suddenly, I felt the car tilt over to an alarming degree. You can see the tow truck getting ready to pull it out. Fortunately, there was no damage to the vehicle.

Troubles with the neighbor

Troubles with the neighbor

This is on the access road to one of our transmitter sites. The station has a legal right of way through this property, however, the neighbor seems to object. I spoke with him and showed him a copy of our deed, he has since changed plans.

One side of a balanced audio connection disconnected

One side of a balanced audio connection disconnected

This is the downside of using category cable to make audio connections. The wires are not as rugged as say Belden 8451. This was causing problems because it is at an AM studio/transmitter site.

Burned 30 amp three phase contactor

Burned 30 amp three phase contactor

Three phase, 30 amp, 240 volt contactor installed in a 480 volt system. Lasted a few years, anyway.

White face hornets nest

White face hornets nest

New tenants on one of our towers. This is a white faced (or bald faced) hornets nest. They are really paper wasps, but that difference aside, these beasts are nasty, aggressive and have a painful sting. Normally, I am a live and let live kind of person, but in this case, they gotta go.

Dummy load attached to plywood

Dummy load attached to plywood

This is at one of our AM clients site. Somebody, quite some time ago it seems, made this test load for a 1 KW AM transmitter. It is very nice, carbon ceramic resistors, 50 ohms and surprisingly little reactance. Then they attached it to this piece of plywood. As one can surmise, the load gets quite hot under full power, full modulation conditions. We remounted this in a cage type enclosure and bolted it to the cinder block wall.

Scala PR-950U cross polarized

Scala PR-950U cross polarized

The client at this station is complaining of intermittent STL drop outs and low signal strength at the receive end. Found this Scala PR-950U antenna mounted for vertical polarization, but the antenna element is horizontally mounted. We’ll call it “vorizontal.”

Ribbon cable from a Cummins 135 KW generator

Ribbon cable from a Cummins 135 KW generator

This was discovered during routine maintenance and thankfully not during a power outage. Mice got into the control box of a newish Cummins 135 KW generator and chewed through what looks like a data buss cable. The generator would not run and the cable and control board needed to be replaced.

Bulging capacitors

Bulging capacitors

There is more bulging capacitors removed from flat panels monitors.

And so on…

Axiom


A pessimist sees the glass as half empty. An optimist sees the glass as half full. The engineer sees the glass as twice the size it needs to be.

Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
~1st amendment to the United States Constitution

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.
~Benjamin Franklin

The individual has always had to struggle to keep from being overwhelmed by the tribe. To be your own man is hard business. If you try it, you will be lonely often, and sometimes frightened. But no price is too high to pay for the privilege of owning yourself.
~Rudyard Kipling

Everyone has the right to freedom of opinion and expression; this right includes the freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers
~Universal Declaration Of Human Rights, Article 19

...radio was discovered, and not invented, and that these frequencies and principles were always in existence long before man was aware of them. Therefore, no one owns them. They are there as free as sunlight, which is a higher frequency form of the same energy.
~Alan Weiner

Free counters!