29 Oct 2010 Friday

Today, I helped begin to clean out of one of the TWR houses. They are preparing to make this house handicapped accessible for a new family who has a child with spinal bifida. TWR will be adding a handicapped accessible bathroom and another bedroom. So, Rhonda Barker and I were removing the linens, dishes, etc. We were checking them over for stains, tears, cracks, etc. We ended up with several bags of discards. If you ever come to visit Bonaire, be sure to bring towels, small rugs, and sheets. They are more expensive and of lessor quality than those from the States. I wish I had realized the need and I would have been sure to pack some in my luggage.

Dead Scorpion -- notice the dead fly for size comparison

I was warned that there were scorpions in that house, so I tried to be careful when I pulled things out of the cupboards, etc. We didn’t see any live ones, but did find a dead one.

I brought home some of the sheets to wash and they came out nicely. Only one set will probably have to become a rag. It was rather tattered.

Larry was supposed to come home a little ‘early’ (before 6:00) so we could find a place to swim. Unfortunately, the transmitter was not working properly, so we will not be going swimming tonight. It is too busy across the street where we usually swim. ‘Happy hour’ is well under way and payday was today.

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28 Oct 2010 Thursday

When I woke up shortly after 6am, I checked the transmitter, via a computer at home, and found there were once again no overnight cutbacks. I increased the modulation another 0.2dBU to 8.3dBu to see if I could induce a cutback. [If it would have cutback, I have the ability to remotely return it to full power] No cutback occurred, so will leave it at this level for tonight.

We managed to contact Nautel today and found that there are some adjustments, not mentioned in the set up procedures, that would bring the no modulation power level with AMC back up to 100kw, instead of 80kw. One of the setup procedures is to set the ‘gain balance’ so there are 0 volts between two specified points. We had done this procedure as explained in the manual. What was not mentioned, is that, after everything is set up and AMC switched on without modulation, this same ‘gain balance’ control can be adjusted, while switching between AMC and ‘standard AM’, so that the power levels are the same. This procedure must be done starting with low power, then repeated while increasing the power in steps to 100kw.

This afternoon, we followed these additional instructions. Now everything seems to function properly on AMC and when switched back to ‘standard AM’. We did some tests switching between the two and found that we could switch quickly from ‘standard AM’ to AMC. Switching from AMC to ‘standard AM’ resulted in multiple faults that shut the transmitter down and it could not be turned on again without shutting off the mains and turning them back on. I then carefully watched what was happening during the switching off of AMC and noticed that the power output would jump to over 130kw. I suggested putting a time delay before the transmitter was allowed to come back on after switching AMC off. This worked, if the delay was over 10 seconds. I then suggested an alternative to switch the transmitter power to 25kw at the same time as switching AMC off, waiting for about 2 seconds, then switching to 50kw. After another 8 seconds, then the switch could take place to 100kw. This way there is dead air for only one second instead of 10 seconds. Two macros, for 50kw and 100kw, was set up to automatically go through this process when switching dynamic carrier control (AMC) off.

Test programming was now successful run with AMC for about 30 minutes. We felt comfortable allowing AMC to be used for this evening’s broadcast. It is now after 10:30pm. The transmitter has been running for 5 hours and seems to be performing well. With this method of dynamic carrier control, AMC, the voltage peaks are considerably less than with ‘standard AM’, so I do not anticipate any problems with cutbacks.

We got our evening swim in tonight. We’ll have to make other plans for tomorrow because it is Friday night AND payday. We suspect there will be a BIG party!

Supper tonight was chicken strips on rice, with green beans, and the rest of the papaya for dessert.

27 Oct 2010 Wednesday

We had another night with no cutbacks, As a result I increased the audio input another 0.1 dBu to 8.1dBu

This morning, like most mornings, I wrote a report to give to Joe Barker on my previous day’s work to have a record of what has been done and report things that have been discovered which need attention.

I also read up on Amplitude Modulation Companding (AMC), which is one of three types of dynamic carrier control available on the Nautel transmitter. It has been decided to use AMC starting shortly, but it does require some special setup procedures before implementing it. Joe plans to meet me at the site at 3pm to go through the setup process. For technical geeks, you can read more about AMC at:
http://downloads.bbc.co.uk/rd/pubs/reports/1988-15.pdf
OR
www.nautel.com/Resources/Docs/Presentations/NAB2009/BECR07_Tim_Hardy_Energy_Conservation_in_AM_Transmitters.ppt

Now that the PA Module is repaired, I have been reading up on other equipment at the site that I have been asked to modify or repair. There is a security system TWR would like to have fully operational. There are also the following functions that would be nice to have added to the remote control system:
1. The ability to switch the tower lights on or off remotely as a backup for the photo cell.
2. The ability to remotely switch off the air conditioner for the transmitter site’s office in the event it is inadvertently left on when everyone is gone. This could save a lot of electricity cost.
3. The ability to check additional voltages on the transmitter that would help diagnose faults, and possibly correct them, remotely.

When Joe Barker arrived at the site, we followed the procedure for setting up the transmitter for AMC. When we enabled AMC, we found that the transmitter power only returned to 80kw instead of 100kw, like it should have without modulation. We decided to call Nautel tomorrow for their advice. For tonight we will continue using standard AM modulation. Once set up, the transmitter can operate with standard modulation or AMC by switching it locally or remotely.

It was nice to swim tonight, especially after missing last night due to the party on the beach. The relatively cool water (82F) cools by lowering body core temperature. Its amazing the length of time one feels cooler after a 30 minute swim!

While swimming, and for some time after we got back to the house, we heard drums and brass instruments playing in the distance. It reminded us of marching band practices at Concord High School that we hear from almost a mile away at our house in Elkhart. We have heard this for several nights, so decided to locate where it was coming from. What a surprise when we found, about a half mile away, a group practicing in the parking lot of a supermarket that was closed. It was a group of about 6 men playing their loudest! Not sure what they were practicing for, but they should be impressive. Maybe we will have a chance to ask them.

For supper tonight we had toasted cheese sandwiches, green beans and papaya (for dessert).

27 Oct 2010 Wednesday

Today was laundry day again. I was afraid it was going to rain, so didn’t get it out as early as usual. It didn’t rain here, but it did a couple of miles up the road. I managed to get a picture of a cute green lizard, probably iguana, hanging on the screened-in porch. He just hung there watching me.

This afternoon, I had Larry drop me at the corner in town and I went shop-seeing. I found a fabric shop that was so neat and pretty. They sell the fabric and will do some sewing there. I also visited some other shops that I had not been in before.

I took a picture of Zeezicht’s where we used to eat on a regular basis. We have eaten there once this time, for old time’s sake. It is now air conditioned and very comfortable.

I also stopped by the fruit market and bought a papaya. The papaya here are different from the ones in Swaziland. The ones we knew in Africa were yellow inside and outside — about the color a cantaloupe is on the inside.

'Old timers' still call it the 'fish market', but now they only sell fruits and vegetables.

The ones we get here are red inside and outside. They are as red as a watermelon and taste a little like guava.

After my two hour walk in town, I am ready for a swim in the ocean. It didn’t look too busy as I walked through the beach area. I did see a big tour bus pull out earlier, so they may be back for some time on the beach and ‘happy hour’. It’s not as enjoyable when the bar area is crowded as we have to walk by it to swim. Everything is outside so the bar is not contained in a small area, it kind of spills all over.

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26 Oct 2010 Tuesday

Can you find the egret? Click to enlarge

In the morning we were in the office. I worked on pictures for the archives a little. After lunch, I went with Larry to the transmitter site where I wiped a few things down and then worked on my quilt and read a book. I

Same egret photo, but cropped and 'adjusted'

also tried to take a picture of the egret that resides at the Transmitter site. The reflection from the water may be to bright for him to show up very well.

I am reading a book, Coffee On the Terrace, by Bruce Grayden. It is a very interesting book about their work with

Beginnings of a quilt, but not for use here!

Wycliffe in the Philippines. It clearly shows how God works in hearts and lives in spite of us and our human frailty.

For dinner, I fixed Indian Mystery Steak, rice and green beans. The mystery steak was nicely seasoned and quite good.

We were unable to go for our usual evening swim as the dock was busy with a party and it was too late to actually drive to a beach. Maybe tomorrow we’ll get our swim in.

NOTE — To see a bigger (and in some cases, expanded)

This steak is no mystery! It's delicious!!

version of any of the images in this blog, just click on the one you want to see.