Sunday, December 28, 2008

Wedding day – Dr Martin Bayes (VR2/AA1ON)


First met Martin (VR2/AA1ON) in April, 2005 when he came to Hong Kong for business. He set up the station in his Fanling office and active in most of the contest.

Today he got married in VR2.

Congratulation to Martin and Queanne!!


Wednesday, November 5, 2008

Heathkit SB-220 Amplifier Meters


I recently had the need for a pair of meters to complete the Heathkit SB-220 amplifier project. I quickly found that these original meters can be expensive! However, I also found there are reasonably price meters available if you don't mind doing a little work to replace the meter face and get them to suit the purpose.

Wednesday, October 8, 2008

Create CB-3F/2K Balun


Yesterday I have problem with my three element yagi - Create 318jr that intermittent of high SWR occur. I dismantled the balun and checked that the colour of the wire changed, may be the result of handling high power all the time. I need to replace another balun or repairing the balun this weekend.

Monday, September 29, 2008

Volta RTTY contest Award


Recently recieved this nice certificate through mail.


Thursday, September 11, 2008

JARL 2008 ALL ASIA DX CONTEST - PHONE


JARL ‘All Asia DX Contest’ is one of my favor contests. The contest period is Sept. 6-7, 2008.
During the contest, stations exchange RS report plus operators' age. I have decided to enter the category as SO20HP, but finally moved to SOABHP. As a result, made 844 QSOs and have the score 82343 points.
The eldest operator age logged is 89 and youngest is 15


Thursday, September 4, 2008

VR10XMT RTTY Award



Here are two RTTY contest awards for the Prefix "VR10".

4X4DK QSL Card



Ami, 4X4DK sent me the QSL card for our six meter QSO. Many thanks.

Thursday, August 28, 2008

AP2DKH QSL Card



W2FB Steve, QSL Manager of AP2DKH sent me the QSL card to confirm the great six meter QSO with Dr. Khalid.


Many thanks.

Monday, July 28, 2008

50Mhz opening to AP and 4X

Good six meter opening to AP and 4X on 26 Jul 08.

Worked:

AP2DKH 0627z 50.163
4X4DK 0638 50.168

Look forward to have more opening soon.

Monday, July 21, 2008

Digital Terrestrial TV Reception

Since the launch of DTT services on 31 December 2007, the first phase of DTT services covers the northern part of the Hong Kong Island, the Kowloon peninsula, part of Shatin and the eastern part of the Lautau Island, amounting to around 50% of population in Hong Kong. My home is located in northern part of New Territories, so need to wait until mid of July, 08.

Last week, I purchased one decoder and connect it to my old "Sony" TV and test the reception before making any decision to but new HD TV set. The decoder start to search TV program when power on and finally all 13 channels were shown up. Signal strength is in between 57-60 % , not bad.

The next step is searching around a suitable HD TV .

Wednesday, July 16, 2008

3-500z flash over


One of the 3-500z experienced with "flash over" problem recently. I am not sure if the tube already damaged or it can re-condition with burn-in procedure apply.

I plug in the tubes (both V1 and V2) into an empty chassis, with only heater voltage connected, no HV. I have observed the V2 (flash over tube) heater not light up correctly, compare with V1.

I have no idea why it is, need to check later.

Monday, July 14, 2008

2008 IARU Contest

Over the contest weekend, the band condition was really terrible. It also happened that thunder storm during the Sunday afternoon time, I need to switch off the radio and unplug all antennas.

Of course, the scores was very poor ...

Monday, July 7, 2008

FT-2000 Remote Keypad



FT-2000 has 4 voice memories, which is a convenient feature for me during contest. However, I find it inconvenient to hit the F1 - F4 function keys with my big fingers. The alternative is to buy the remote keypad FH-2, but consider it is very expensive.

Information from the net that the keypad is a combination of push button and resistors, which make it as voltage divider and it is the same as the previous model FH-1, see attached circuit diagram and resistor values.

The original FH-2 keypad has 12 buttons, which are for other functions. My application is for F1-F4, so I decided to make the keypad as simple as possible by using a plastic box, with 4 push buttons. It works fine and ready for the IARU contest.






Tuesday, July 1, 2008

RDXC 2007 Award


I am happy to receive the RDXC 2007 Award.

13th Place - World and of course Country Winner, because no other VR2 participate in this Category.


I3VHF - Baby Loop Antenna



Recently I got the I3VHF Baby loop antenna from Horst, VR2BT. He is going to move QTH and no more room for this antenna. The loop antenna is quite heavy and well designed. Control open and close to the variable capacitor by using a mouse connected to the controller.
I have installed it today. It works fine from 10M to 40M, performance close to the dipole.

Saturday, June 28, 2008

Six Meter Open to EU

At 0659z , six meter open into EU.
SP8AWL replied to my CQ call on 50.115 Mhz. Then followed with SP7CDG at 0702z.
At 0723z, SV2DCD coming up.
This is the first time EU QSO in Cycle 24.

Tuesday, April 22, 2008

FT-2000 FSK connection

Last week, I connected the FT-2000 with my homebrew interface, which use the opto coupler 4N32, for RTTY FSK keying. Calling CQ for quite some time without any reply and finally find out thatI wasn't getting any shift.

I've used this interface on other radios over the years with no problem, including FT-920, IC756pro and FT-990. Finally I solved the problem, by the help / information from one of the member in the FT-2000 newsgroup .

The 4N32 opto coupler has a 0.50 volt plus collector "on" voltage which is OK under the usual TTL "low" state and has keyed all my other radios with no problem.

The FT-2000 requires the low or "ON" state to be less than 0.4 volts in order to key the FSK line.

I replaced the 4N32 by a 4N37, which has 0.3 saturated voltage (VCE sat) and it works perfect now.

I believe the FT-2000 is the first of the Yaesu radios that makes extensive use of 3.3 volt (low power) CMOS logic. The "low" requirements of the low power CMOS devices is considerably less than the old CMOS and TTL (most of which worked below about .65 volts). The standard for low power CMOS is down around .3 volts

Wednesday, April 16, 2008

C52C - The Gambia 2007 DXpedition

I am one of the lucky station in Hong Kong worked C52C on 40M in the Gambia 2007 DXpedition operated by the OM0C contest team. On 24 Oct 2007, by chance I can stay a little bit longer at home early in the morning, normally I need to leave home at 2200z. I made the contact with several calls, two many competitors (JAs).

Today I received the nice QSL card.




Wednesday, April 2, 2008

CQ World Wide WPX Contest - 2008

Over the weekend, participate in the CQ World Wide WPX Contest, 15M High Power category. The propagation on the first day was terrible, no signal heard from EU, but JAs are workable. The score on the first day was very low and only achieved approx. 300,000

In the morning of second day , the situation was almost the same, and could only work JA, YB, BY, UA9 and with several station from Pacific.

In the afternoon, start from 0700z, EU signal going up and maintained good condition until 11:00z. I am very lucky to catch this opening and boot up my score just over my last year record. Final at 865,686

The equipment used during the contest are:

Yaesu FT-2000

Create 318jr

Heathkit SB-220






Tuesday, April 1, 2008

2006 UK RTTY Contest Award


The award finally arrived on today. I need to wait more than two years for this nice colourful award issue by GM4FDM.

Monday, March 17, 2008

Russian DX Contest 2008


Over the weekend, participate in the Russian DX contest all band-phone.
I have been in this contest started from 2005 and have fun with it.
With the low solar activity, band condition was poor. My score not as good compare to last year.

Tuesday, March 11, 2008

TX5C

With a simple trap dipole,which is only two meters high on the roof, I was lucky to catch TX5C on 40M at 1428z on 9 March. It is very difficult becasue of JA wall. I need to call almost for an hour to get it, new one for me on 40M.

I hope to have them in the log on 20M and 17M. Watch and wait for good propagation ...

Wednesday, March 5, 2008

Palestine E4/OM2DX




The QSL card arrived yesterday.

Band condition was poor lately, only worked them on 20M.

Tuesday, March 4, 2008

Porsche and Jade with RED PACKETS


As promised, Martin and Anni gave Porsche and Jade the "RED PACKETS" for the year of RAT. They like it very much but Jade walk away when taking photos !

Monday, March 3, 2008

Six Meter SB-220 Rebuild






Steve, VR2XMQ gave me the SB-220 when the time he moved QTH. The amplifier was modified to six meter by one of the ham in the United States. However, the amplifier experienced with problem since it arrived. In the first instance, the HV meter was damaged in shipping and flash over when switch on, which finally proved one of the 3-500z have problem. The outlook of the amplifier was bad, most of the screws are rusted and internal wiring is in a mess, overall it is not a professional workmanship.
The amplifier was sit there for sometime and few weeks ago, I decided to re-build the amplifier and make it ready for cycle 24 for some DX in the magic band.
Here below are the major improvements:
1) repainted the power and filament transformer and inside chassis
2) replace most of the rusted screws
3) replaced all eight HV filter capacitors to 270uf 450V 105 degree C
4) replace the HV rectifier board completed with eight 1N4007, which used as the 5.1V bias zener diode
5) replace two panel meters
6) replace the load capacitor
7) add soft-start and soft-key
8) replace the burnt safety choke (8 mm Teflon rod with approx. 60 turn of SWG 22 wire.)
9) replace one 3-500z
10) refine the input SWR
11) tidy up all internal wiring

With AC mains supply at 207V, it gave out 900W with 100W drive. It can be more if AC voltage up a little bit. Now it is a 100 percent working amplifier and ready to go.

WPX Phone Contest 2007


Another achievement for WPX Phone contest 2007. I am very surprised to be no.1 in Asia for 21 MHz . I will participate in this year contest again, still not decide which band to go, may be 14 MHz?

Tuesday, February 12, 2008

Contest Award


Very happy received ARRL International DX contest Award 2007 on today.

Monday, January 7, 2008

Power-on delay PCB


I made a new power-on delay relay circuit (soft-start) PCB yesterday. The zener diode which create a high turn on voltage for the Darlington connected transistor pair. The delay is approx. 3 seconds using 47K resistor and 100 uF capacitor. Longer delays can be obtained with a large capacitor.

Saturday, January 5, 2008

GI7B Six Meter Amplifier Project - Update 9



It is connected to a BIRD Dummy Load (Model 8401) and 43 Watt Meter and easy tune to approx. 700W output. End of the project. Look forward to hear you on the magic band.