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20060301 2006 March 1

Posted by kc2ped in Uncategorized.
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Here are the specifications for the Kenwood TH-D7A(G) Data Communicator FM Dual Bander:

Frequency Range
144 MHz440 MHz
TX: 144-148 MHz
RX: 118-174 MHz
TX: 430-450 MHz
RX: 400-480 MHz
Mode F1D, F2D, F3E (FM)
Operating Temperature Range -20°C to +60°C (-4°F to +140°F)
Antenna Impedance 50 ohms
Power Requirement External power supply(DC in) 5.5 to 16.0 V (13.8V)
Battery terminals 4.5 to 15.0 V (6.0 V)
Current transmit with HI, 13.8V (DC IN) VHF (Approx. 1.7 A) UHF (Approx. 2.1 A)
Current transmit with HI, 9.6V (battery terminals) VHF (Approx. 1.7 A) UHF (Approx. 1.8 A)
Current transmit with HI, 6.0V (battery terminals) VHF (Approx. 1.3 A) UHF (Approx. 1.5 A)
Current transmit with EL, 6.0V (battery terminals) Approx. 330 mA
Current receive standy (TNC off) Approx. 45 mA
Dimensions (W x H x D)
[projections not included]
2.25 x 4.75 x 1.5 inches
[with included PB-38 battery]
Weight 12 oz (340 g)
[with PB-38]
Ground Negative
Microphone Impedance 2 k ohms
Maximum Frequency Deviation ±5 kHz
Modulation Reactance modulation
Modulation Distortion Less than 3% (300 Hz – 3 kHz)
RF Output Power (approx.)
HI (13.8V DC)
HI (9.6V)
HI (6.0V)
6 W (VHF), 5.5 (UHF)
2.5 W (VHF), 2.2 W (UHF)
0.5 W
50 mW
Spurious Radiation Less than -60 dB
Audio Output Power
9.6 V (10% distortion)
6.0 V (10% distortion)
More than 450 mW
More than 300 mW
Circuitry Double conversion superheterodyne
Intermediate Frequency VHF/UHF
1st IF
2nd IF
38.85/45.05 MHz
450/455 kHz
-6 dB
-40 dB
More than 12 kHz
Less than 28 kHz
Sensitivity (12 dB SINAD) Less than 0.18µV Main, 0.28µV Sub
Squelch Sensitivity Less than 0.1µV
Kenwood follows a policy of continuous advancement in development.
For this reason pecifications may be changed without notice.
These specifications are guaranteed for Amateur Bands only.

I understand what most of the categories are about but I have no idea how good most of the values are.

The above table looks great in a regular browser window and even in WordPress when I am writing the post, but the CSS or whatever is keeping it from displaying properly. Or rather it is displaying it in the way it thinks is proper. So blank lines that are necessary to align categories and values are being surpressed as are the table borders that would make the table so much easier to read. I am not sure WordPress is going to work for the way I like to create blog entries. I want more control over the way my content is going to be displayed that they want to give me.


20060227 2006 February 27

Posted by kc2ped in Uncategorized.
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I took the General exam tonight at Columbia University and passed it with five questions to spare. Two of the other members of my Technician class were there to take and retake that exam and both passed it. Another two members of the class didn’t pass. So Now I either have to wait for the FCC to do away with the Element 1 requirement for the General license, or learn code. My Certificate of Successful Completion of Examination is good for 365 days so I am going to wait them out until the end of the year. I still don’t have a radio to use with the license I already have.

But I have another new possible logo:

20060226 2006 February 26

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I just got back from the Bronx County ARES meeting which, it turns out, wasn’t scheduled for today, as the web page indicated, but is held on the second Saturday of the month. This is going to conflict with my Map Society meetings. I will have to listen in on the weekly NYC district ARES net, which happens at the same time as the NYC ARECS net.


I modified the antenna connected to a ground by a coil of wire in a triangle logo that seems to be the generally accepted logo for amateur radio to make it my own. I am not happy with the way it displays in the blog header so will have to work with it some more. When I view it in Photoshop it is fringed in blue rather than the white that appears here. It is strange that it reacts that way in the header because both graphics were created from the same file. The only difference is that this one is full size.

20060224 2006 February 24

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Today I registered my intent to take the General exam on Monday with the VEC at Columbia University. I was up to an all day average on the HamTestOnline simulator of 90% yesterday. Today I went to the library to abuse the T1, update my web page, and do some studying. My batteries died after I had only taken one exam and gotten part of the web page updates done. The first exam of the day I passed with a few questions to spare. My plan is to take a bunch of practice exams during the day on Monday since my score seems to go up after having taken several of them. Hopefully that will get me primed for the real deal Monday evening.

On the way home tonight I stopped at the newsstand in the lobby of the MetLife building where I usually get Popular Communications magazine. They did not have it tonight so I got CQ Amateur Radio Communications and Technology, which is more apropos anyway since it is about two-way communications and Popular Communications is only about monitoring. CQ has a market survey of UHF/VHF handhelds. They give a lot of column space to the Kenwood TH-D7A(G) in their most expensive radios section and don’t have anything bad to say about it. But then they didn’t have anything bad to say about any of the radios they reviewed. I am sure that the good reviews and the fact that all of the radios reviewed were manufactured by a company that has at least a full page ad in the magazine is purely a coincidence.

20060220 2006 February 20

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I designed a tentative QSL and business card tonight.

The graphic is clipart downloaded from Microsoft. Someday maybe I will be able to find one of my own photographs to use there.

So far I have only printed one sheet of the business cards and found that I tagged the wrong key when entering my ZIP Code so had to pen in a correction. They will get me by until I decide what I really want to do. And if there is a possibility of getting a General license and a new call sign I don’t want bunches of old cards hanging around here. I already have hundreds of other old cards and can’t read enough books to use them up as bookmarks. I am going to try to restrict my QSL activities to electronic cards from eQSL.cc.

This afternoon, while taking a break from my General exam studies, I searched the Web for “local” ham events. I only found two. One is a convention of Filipino operators in Queens and they want $85 for the event so that one is out. The other is two field days sponsored by the Hall of Science ARC in Corona Park. Researching more deeply I found that they have monthly meetings that are open to the public. They are on the second Tuesday of the month from 2000 to 2200 ET. I don’t have anything on the calendar for that evening next month so I will check them out. It is a bit of a truck from here, two buses or a bus and train, or two trains. The web site doesn’t have any travel directions so I am going to have to search the satellite imagery on Google Local and see if I can figure out what bus goes there from Main St, Flushing.

I have been taking a bunch of practice exams at HamTestOnline.com. I like them better than the ones at QST.com because the answers aren’t always in the same place when you see the question on subsequent tests. Also, at the end of the test they tell you which sub-elements you are having trouble with. The only one that I am all over the place in that regard. But I am averaging 82% overall. Hopefully by the end of the week I will have that bumped up into the 90s so I have a bit of a buffer in case I get real unlucky again in which questions the ask.

20060219 2006 February 19

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I did some research today to see if a radio could be interfaced with anything using Bluetooth. My idea was that I could use VOX technology and a cell phone headset to talk over the radio or even send packet messages from a PDA. I found CTR-Remote which allows you to control a radio from a PC or a Pocket PC. You can get from the same company, a Bluetooth interface which would work with the Kenwood TH-D7A(G). I emailed them to see about it and they say it should work but that I would probably have to supply power to the Bluetooth device as they don’t know if the radio will do it for me.


I also found a guy in England who has a web page describing using the TH-D7 with a Pocket PC running APRSCE software (I think it comes from TAPR) to do APRS.


20060217 2006 February 17

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As of noon today there has been one new license issued. They just issued KC2PDX to an emergency management office somewhere. With only two letters left in this cycle it is almost certain that I will get a KC2PE_ call. That is going to be a little awkward for me to enunciate clearly. P and E sound very similar and so do B, C, D, E, and G which could be the last letters of the call sign. I hope I can pass the General exam and that they abolish the Morse code requirement before I get on the air so I can start using a General call sign right away and am luckier in what one I get.


I got down to Barry Electronics and picked up the General exam study guide which is only $17 as compared to $20 for the Technician guide. It is a smaller form factor as well. Now it is the same size as a computer manual where the Technician guide was 8.5×11″.I also talked to Jonathan some more about the Kenwood TH-D7A(G). He says he has never had any complaints about the radio in any regard but also says that it isn’t a big seller because if its niche market.


The license has finally been processed. As of 1600 EST today I am now


The call sign isn’t too hard for me to get my mouth around and is kind of appropriate since I want to use a handheld radio while mobile.

20060216 2006 February 16

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I went down to Barry this afternoon to buy the General study guide and was greeted by a sign taped to the door saying that they were going to be closed this afternoon. So no study guide.

This stuff about the FCC database being updated daily at 0200 is bogus. Well maybe it is accurate somewhere in the world, but it isn’t here. As of midnight last night the last license listed was KC2PDP which was issued yesterday. As of 0230 this morning that was still the last license issued. And as of 1200 today there had been no additions to the list. I checked at around 2200 tonight and the last license is now KC2PDW which was issued today. Although the site says their downtime is “Daily: 12 Midnight – 2 AM ET” I suspect that the database gets updated at 2400 UTC which would be 1900 EST and at the end of the federal flex workday. There is no point in staying up into the middle of the night anymore.

20060215 2006 February 15

Posted by kc2ped in Uncategorized.
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I have started staying up until 0200 to check the FCC database and see if my license is listed there yet. The FCC takes their database down at midnight each night to update it with the day’s processing and makes it available again at 0200. It is a crazy thing for me to do since I don’t have a radio to use it with if I find that it is there, but I am doing it anyway.

I have started a couple of Ham mapping projects. I found the online NYC repeater directory that is compiled from real reception reports rather than FCC database entries. So I have been databasing the call signs and frequencies from it then going to QRZ.com to get the longitude and latitude. The positional information is real crude since it is based on the mailing address of the responsible party rather than the antenna location and I have already found a Manhattan repeater that is associated with someone who gets their mail in Westchester. It appears that QRZ uses only the ZIP Code when they geolocate the site as almost all the licensees in my ZIP Code are listed with the same Lat/Long. That is my second project. I am databasing all of the local hams to use for networking. I searched the FCC database for all active licenses and then went to QRZ to find out where the person lives and what level of license they have. I also collected the number of QRZ searches for the call sign figuring it might give an indication of how active the user is. The guy with the most searches is a technician and some of the extra operators are near the bottom of the list. The next step is to figure out how to get Access to write a report wrapping the data in the HTML I need to make a Google Local map. This is a test project to see if I can figure out how to make point maps since I have a new feature request for my occultation maps web site.

I have been taking a lot of General practice exams online at QRZ.com and am scoring around 80% most of the time. Most of the questions I can reason the answer after they give me the right one, but some of them are beyond me. I don’t like studying this way. I want to understand the principle rather than being able to parrot the correct answer to the question. I am going to have to get down to Barry Electronics and buy the study guide, the library doesn’t have that one.

20060212 2006 February 12

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When I got downtown today I began to wonder if the Staten Island ferry would be running so the instructor could get to class but he was there. We did get a full-fledged blizzard with heavy snow falling horizontally and whiteout conditions. It looks like our total accumulation is around 18”. Several students didn’t show up and one of the instructors didn’t either. But the volunteer examiners did.

I passed the exam but not by the margin I should have. I got 29 of 35 questions right or 82.6%. There were at least three questions on the exam that I have never seen before. Two other students said the same thing but I don’t know if they have spent as much time taking practice tests as I have. Only one of the students from the class failed.

I took the General exam right away and failed it by only one question. I am being encouraged to spend the next two weeks taking practice exams and to retake the General on 20Feb06 at Columbia University.

They said that our call signs should appear in the FCC database by next weekend.