Search found 1823 matches

by VK4GHZ
Tue Nov 12, 2019 11:13 am
Forum: 1296, Microwaves and Opto
Topic: Inside the RF HamDesign feed
Replies: 4
Views: 61

Re: Inside the RF HamDesign feed

I was a little disappointed with the performance of my RF Hamdesign tri-band (3.4/5.7/10 GHz) ring feed, but I guess they should be considered as being a compromise (with questionable performance) vs optimised single band feeds. Fun to play with, but as Chas points out, they are not particularly che...
by VK4GHZ
Sat Nov 09, 2019 6:39 pm
Forum: Ancillary, Test Equipment, Components & Parts
Topic: Video: Back to Basics: Diodes
Replies: 0
Views: 41

Video: Back to Basics: Diodes

Another informative video from Alan, W2AEW. This video is a Practical Guide to Diodes - their basic operation, IV curves, typical characteristics, various diode types, and common diode specifications. Links to many of my previous videos involving diodes are mentioned, so these links are included bel...
by VK4GHZ
Sat Nov 09, 2019 6:34 pm
Forum: Ancillary, Test Equipment, Components & Parts
Topic: Video: Back to Basics: Potentiometers - WARNING!
Replies: 0
Views: 78

Video: Back to Basics: Potentiometers - WARNING!

Another informative video from Alan, W2AEW.
This short video discusses the main differences between controls and trimmers/trimpots - including one VERY important difference that many people don't know about, or think about.


https://www.youtube.com/watch?v=5d_TTQ2OJtM
by VK4GHZ
Sat Nov 09, 2019 6:16 pm
Forum: General Discussion
Topic: Kings Generators
Replies: 2
Views: 114

Re: Kings Generators

Although we live in disposable society these days, replacing a 'cheap Chinese' something with a different 'cheap Chinese' something often ends the same. The URL you posted appears truncated (returns a 404 error), and should probably be: https://www.4wdsupacentre.com.au/adventure-kings-2kva-generator...
by VK4GHZ
Thu Nov 07, 2019 7:44 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - SEQ-9700 relay outputs
Replies: 11
Views: 402

Re: Survey - SEQ-9700 relay outputs

Hi Bo This sequencer has been specifically tailored to suit the IC-9700. The 9700 is a unique class of Icom radio with the quirks of the 'Main' and 'Sub' bands and Sat Mode, etc. As I don't own an IC-7300 (or an IC-9100 for that matter) I wouldn't be able to customise the firmware to suit accordingl...
by VK4GHZ
Thu Nov 07, 2019 2:14 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - SEQ-9700 relay outputs
Replies: 11
Views: 402

Re: Survey - SEQ-9700 relay outputs

I'm not sure what I was thinking! It occurred to me, after moving umpteen parts to the other side of the PCB, the solder paste stencil that has been made to suit the current revision PCB would be rendered useless. So, I have removed the PCB trace from the 13.8V supply (sourced from the IC-9700) to o...
by VK4GHZ
Mon Nov 04, 2019 12:32 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - SEQ-9700 relay outputs
Replies: 11
Views: 402

Re: Survey - SEQ-9700 relay outputs

What would be the current limit on the in and out lines (?) - presumably limited by the size of the board tracks to the DB15? Hi Peter Yes, the current limit would be determined by the PCB trace width and length. The underside of the PCB is rather 'busy' with many components and traces, and this tr...
by VK4GHZ
Sun Nov 03, 2019 1:21 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - SEQ-9700 relay outputs
Replies: 11
Views: 402

Survey - SEQ-9700 relay outputs

Hi all The SEQ-9700 sequencer provides the following nine relay outputs: * 144M PA * 144M LNA (I use the term LNA, but interchangable with mast head preamp, etc) * 144M Antenna Switch * 430M PA * 430M LNA * 430M Ant Sw * 1200M PA * 1200M LNA * 1200M Ant Sw All of the these relay outputs are independ...
by VK4GHZ
Wed Oct 23, 2019 1:41 pm
Forum: 144 & 432 MHz
Topic: Mt Mobilin Beacon VK4
Replies: 2
Views: 817

Re: Mt Mobilin Beacon VK4

I cannot hear it in Brisbane right now. If I check the Brisbane VHF Group website homepage, we see this, dated 2016: oldinfo.png If you dig a bit deeper you then find this: whoknows.PNG So who knows? And nobody from the BVHFG posts on Forums anymore. Apparently, it's too hard to use Forums and Faceb...
by VK4GHZ
Wed Oct 23, 2019 11:33 am
Forum: 1296, Microwaves and Opto
Topic: 23 on 23 Wednesday 23 October 2019
Replies: 3
Views: 932

Re: 23 on 23 Wednesday 23 October 2019

Only running a vertical here, so I'll be listening on 1294.0 and VK4RMC 1273.5 MHz FM.
[Note that 1204.0 is a repeating typo, and out of band!]

Dunno what the Facebook zombies are doing, and don't really care! :lol:
by VK4GHZ
Thu Oct 10, 2019 8:21 am
Forum: Ancillary, Test Equipment, Components & Parts
Topic: BG7TBL GPSDO (GPS Disciplined Oscillator) and 10 MHz Distribution Amplifier
Replies: 4
Views: 758

Re: BG7TBL GPSDO (GPS Disciplined Oscillator) and 10 MHz Distribution Amplifier

For BG7TBL GPSDOs, this EEVBlog topic should be considered as a "master reference". https://www.eevblog.com/forum/testgear/bg7tbl-gpsdo-master-reference/ It's long, but has lot's of useful information for the many variants of the BG7TBL GPSDO. :shock: With regard to which OCXO is fitted, it's a luck...
by VK4GHZ
Sun Oct 06, 2019 5:40 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - IC-9700 transverter operation
Replies: 16
Views: 3986

Re: Survey - IC-9700 transverter operation

Some rough 'n ready wobble-cam (phone) video demonstrating the SEQ-9700 'Transverter Mode' frequency offset with the prototype.



The actual touchscreen is mounted to the front panel of an old(er) prototype version, which is why it looks a bit shabby!
by VK4GHZ
Sun Oct 06, 2019 2:32 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - IC-9700 transverter operation
Replies: 16
Views: 3986

Re: Survey - IC-9700 transverter operation

Thank you to everybody who went to the effort of posting a response. I didn't realise there were so many that used 144 as an IF. Perhaps the 432 IF is a VK4 thing? ! With the limited amount of 4MB touchscreen RAM I have left to play with, this is how the Set > Transverter page will look like: Survey...
by VK4GHZ
Fri Oct 04, 2019 4:27 pm
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - IC-9700 transverter operation
Replies: 16
Views: 3986

Re: Survey - IC-9700 transverter operation

Adam, You mention offset for 10 Ghz transverters based on a 70cm IF. A significant number of transverters likely to be used for 10Ghz would have an IF on 2 metres. DEMI 10GHz base model is 144-146 IF - 432-434 only by special request. KUHNE MKU 10 G4 PROF, 3 cm Transverter - 144-146 or 432-434 opti...
by VK4GHZ
Fri Oct 04, 2019 11:31 am
Forum: SEQ-9700 Sequencer OFFICIAL Forum
Topic: Survey - IC-9700 transverter operation
Replies: 16
Views: 3986

Survey - IC-9700 transverter operation

The SEQ-9700 sequencer is in the final stage of development. This survey is asking IC-9700 owners three questions: 1) Do you currently use, (or plan to use) 1296 MHz on your 9700 as an transverter IF at all? 2) Do you currently use (or plan to use) 144 MHz on your 9700 as an IF for bands above 5.7 G...
by VK4GHZ
Sat Sep 28, 2019 11:41 am
Forum: 1296, Microwaves and Opto
Topic: Bouncing radio signals off the Moon? Yeah, but on 10 GHz?
Replies: 2
Views: 1023

Re: Bouncing radio signals off the Moon? Yeah, but on 10 GHz?

Thanks Hayden & Richard.

An informative video that is far superior to the usual vague 'wobble-cam' type crap that Facebookers upload directly to FB (which then stays within the FB bubble).

That 'Yakety Sax' track never gets old! :D
by VK4GHZ
Mon Sep 23, 2019 10:23 am
Forum: Transceivers, Transmitters & Receivers
Topic: FT-817 front BNC fault
Replies: 8
Views: 1480

Re: FT-817 front BNC fault

Hi Hayden Ask yourself, will you ever use the front BNC? If it's sitting on top of a transverter box (or integrated into a transverter, like mine), then probably not. After removing the relay, you could just jumper the relay contacts to the rear connector. Saves the cost and hassle of replacing the ...
by VK4GHZ
Mon Sep 16, 2019 6:56 pm
Forum: Ancillary, Test Equipment, Components & Parts
Topic: For Sale: SMA failsafe relays 18 GHz 28V
Replies: 1
Views: 746

For Sale: SMA failsafe relays 18 GHz 28V

For Sale: I have two Transco 82152-919C70100 and one DowKey 401-2308-4 SMA failsafe change-over relays. Trivia: These are essentially the same relay, as the parent company owns Dow-Key, K&L Microwave, and Transco. • 18 GHz rated • very good condition. • 28VDC operation (no latching or funny business...
by VK4GHZ
Mon Sep 16, 2019 4:56 pm
Forum: General Discussion
Topic: ARRL free articles
Replies: 0
Views: 1099

ARRL free articles

FYI... Most months the ARRL has a free article to whet your appetite which can be downloaded by non-members. http://www.arrl.org/this-month-in-qst Click on the + to expand that month's offerings, and click on the appropriate link to download the PDF. Worth keeping an eye on! :shock: ARRL-free-articl...
by VK4GHZ
Mon Sep 16, 2019 4:49 pm
Forum: 50 MHz
Topic: FT8 6m DX
Replies: 40
Views: 12595

Re: FT8 6m DX

FYI...

The ARRL has a free article from the September 2019 issue of "QST" available for download:

Enjoy FT8 from almost anywhere

http://www.arrl.org/files/file/QST/This ... Witmer.pdf

:om2: