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How to simplify logging?
Forum: Digital Modes
Last Post: VK2CSW
28-04-2024, 02:43 PM
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» Views: 1,342
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7285kHz AM?
Forum: Off Topic!
Last Post: VK3RX
25-04-2024, 01:16 PM
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VK3XPD 23cm 65W modules
Forum: 1296MHz, Microwave & Opto
Last Post: VK2AZ
22-04-2024, 09:34 PM
» Replies: 1
» Views: 476
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Dud Headphone Jack on Yae...
Forum: Transceivers, Transmitters & Receivers
Last Post: VK2CSW
20-04-2024, 07:53 AM
» Replies: 1
» Views: 674
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23-on-23: Tuesday April 2...
Forum: 1296MHz, Microwave & Opto
Last Post: VK4CZ
19-04-2024, 01:22 PM
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» Views: 1,042
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Audio Clipping on Sideban...
Forum: LF, HF, MF
Last Post: VK2CSW
17-04-2024, 08:27 PM
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» Views: 1,450
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FTDX101D & SCU17 ?
Forum: General Discussion
Last Post: VK4TS
16-04-2024, 10:50 AM
» Replies: 1
» Views: 769
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Wiring a microphone for h...
Forum: Homebrew
Last Post: VK2CSW
15-04-2024, 07:47 PM
» Replies: 7
» Views: 3,534
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Dipole for 6m
Forum: 50MHz
Last Post: VK2CSW
15-04-2024, 07:10 PM
» Replies: 6
» Views: 2,617
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Toroid Supplier/s
Forum: Ancillary, Test Equipment, Components & Parts
Last Post: VK2CSW
11-04-2024, 06:26 PM
» Replies: 3
» Views: 1,707
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VKCC Groups IO |
Posted by: VK4TS - 04-09-2018, 01:25 PM - Forum: Contests, Field Days, Portable Operation, JOTA, SOTA
- No Replies
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VKCC Groups IO
Many yahoo groups have moved over to the Groups IO format. We have setup a groups.io account
for the VK Contest Club.
The advantage of Groups IO is listed as: - Integration with other services, including: Github, Google Hangouts, Dropbox, Instagram, Facebook Pages, and the ability to import Feeds into your groups.
- Businesses and organizations can have their own private groups on their own subdomain.
- Better archive organization, using hashtags.
- Many more email delivery options.
- The ability to mute threads or hashtags.
- Fully searchable archives, including searching within attachments.
The founder of Groups IO was the originator of the Yahoo groups platform Mark Fletcher.
To join the VKCC Groups IO email reflector simply: email vkcc+subscribe@groups.io
There are currently around 30 VK and ZL contest types on the email reflector.
Have a great day
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Attachment sizes |
Posted by: VK5TM - 31-08-2018, 01:05 PM - Forum: General Discussion
- Replies (2)
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This will be just me not being able to find something I suspect, but is there (well, I thought I saw), a post or similar describing the size of various attachments that can be posted?
Tried the search function and looked at 'Help' but didn't find anything.
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To go from here to there |
Posted by: VK4TS - 31-08-2018, 08:07 AM - Forum: General Discussion
- Replies (2)
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What would take you to go from here (general) to there (contesting)
We are all time poor even those who are retired.
Would a series of short,maximum two hour contests, interest you enough to get the radios fired up ?
Alan VK4SN has created a special contest scoring website used for the Trans Tasman and the RD this year.
It allows all sorts of fun events like a Where's Wally contest - where the major multiplier is working a guy called Wally
Put your thinking caps on and lets create some reasons to get on air - short and sharp is better than not at all
73
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Items for Sale |
Posted by: VK2EZT - 15-08-2018, 12:46 PM - Forum: BUY and SELL
- No Replies
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Hey all,
I am selling a fair few items which will be making their way onto the list. Theres a 'lot' of goodies that will be uploaded on the site.
https://ezat.id.au/index.php/products/
by all means I am not running a business here and most of the price tags are what i paid.
Just have bits and pieces that i require to sell and make room.
The Shimizu SS-105s transciever is up for sale. Brand new and never used which is a very rare find.
Regards,
Ezat
VK2EZT
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2018 RD Contest |
Posted by: VK4ADC - 12-08-2018, 07:35 AM - Forum: Contests, Field Days, Portable Operation, JOTA, SOTA
- Replies (3)
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The RD Contest is on this weekend and I have already done my operating time. I used VKCL 4.60 as the latest version, exported the Cabrillo log and then tried to upload via the link in the RD rules. Reject.
After you do the cabrillo export from VKCL, you need to add the following up near the top of xxxx.LOG (your callsign.log) file :
CATEGORY-OPERATOR: SINGLE-OP
CATEGORY-STATION: FIXED
CATEGORY-POWER: HIGH
CATEGORY-MODE: SSB
CATEGORY-BAND: ALL
Vary these entries to suit your operation - the list of optional settings is in http://www.wia.org.au/members/contests/r...tRules.pdf
Save the edited file.
The log upload link is
https://contester.azurewebsites.net.
Browse to xxxx.LOG in (eg) c:\VKCL4xx\Contests\2018\RD
Submit.
Accepted. Browser page updates to show your log details..
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Tx Fault on IC-7400 / IC-746Pro |
Posted by: VK4ADC - 08-08-2018, 03:36 PM - Forum: Transceivers, Transmitters & Receivers
- No Replies
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My IC-7400 has been on and off the workbench since late last year while trying to obtain replacement transistors (/FETS) for the PA driver area. One semiconductor at a time, I have replaced the pre-pre-driver, the pre-driver, and finally the driver devices before it is back in operation. The original fault was varying Tx power band by band - like 2W on 50MHz, 80W on 14MHz, 25W on 1.8MHz, so it wasn't entirely dead, just bad news.
A complication was that the driver PCB was damaged when one of the driver FETS caught fire late in the repair process - yes, it was like a candle - and accompanied by the normal bad smell. It was upside down on the bench with the bottom cover removed so I was able to see it directly. Fortunately I had looked at the power supply current too and it was up around 10A on receive (instead of 2A). The power switch was turned off quite promptly while I investigated, accompanied by some muttered bad words of course !!
Google showed a definite lack of B5703B driver PCBs to be able to replace my damaged PCB so armed with a micrometer and a PCB layout from the service manual zoomed to 600%, I did a will-fit PCB layout, etched and transferred the basic SMD capacitors and the couple of 150R resistors to it. The bias SMD components were replaced with new.
The issue is getting the driver FET's source connection to solder to the heatsink. The first time I did it, from the top with a hot air gun, and it wasn't solid / good. The second time, I placed the heatsink on an upside down clothes iron (on max heat) and once the solder on the 'source tongues' was melting, popped the driver PCB over the source slots using long nose pliers and then carefully slid it sideways off the flat of the iron onto a piece of wood to let it cool down.
The original driver devices were 2SK2975's but these don't seem to be available now. There are a few articles on the web that refer to using RD07MVS1 devices in lieu. These FETs are no longer readily available unless you want to buy fakes out of China or Hong Kong BUT the recommended Icom replacement seems to be the RD07MVS2-T112, Icom part number 1560001232. You won't find them listed too often either but at least there is a greater likelihood to find some available. Not super cheap, but better than discarding an otherwise good radio.
I used two of these RD07MVS2 devices (push-pull design) and now have 100W on all bands 1.8 to 50MHz, the RF power is down around 60-70W on 2M (should be 100W), so these devices do work. The bias was set for a driver current of 1.5A (see the other web articles re this setting), down from the original 2.5A in the service manual. I haven't gone back to try trimming the 2M power up or going through the full PA adjustment procedure pending seeing if the new driver FETs survive. They are running pretty cool at the 50% duty cycle of FT8 and 100W out on 14 MHz for part of most days over the last two weeks so it looks promising.
The reason for this post is to give others with similar problems a bit of light at the end of the tunnel. Yes, there is often a fix. Even if it not an easy fix!!
Doug
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Amplifier for 6 meters |
Posted by: VK4BVI - 08-08-2018, 11:55 AM - Forum: 50MHz
- Replies (10)
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Just out in the shed rummaging through some bits 'n pieces, and came across an old commercial VHF amplifier, almost intact.
The thing that caught my eye was an MRF492, which is the final output device.
Anyone had experience in using these devices in 6 meter amplifiers? They are good for about 70 watts or so.
Before the 'Gee it's an old piece of gear' brigade starts up, yes I know its old but, I am not interested in a commercial amp, I am going to home brew my own.
Just looking for past experiences from those who have been there, done that.
Ron
VK4BVI
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SK - Paul Hayden VK4ZBV |
Posted by: VK4OE - 06-08-2018, 05:49 PM - Forum: Silent Keys
- Replies (2)
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Greetings to all readers.
Paul Hayden, VK4ZBV, one of the widely known radio amateurs of long standing in the Brisbane region, passed to his rest last Friday after an illness, and his funeral and life-celebration will commence this coming Friday at 12:00 in the chapel at the Mt Gravatt cemetery.
His bereaved wife telephoned me this afternoon and was pleased that I offered to notify various ham radio media of Paul's passing.
Paul was one of those quiet technical 'whizzes' and was able to fix nearly any complicated radio or test instrument. Quite a number of local fellows will remember Paul and will be saddened by this news.
Cheers and 73,
--Doug Friend , VK4OE.
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