Calling "CQ" ..... The Knole DC 40m Receiver Kit Build

[raynerd]

I ordered the Knole DC RX a couple of week back from http://www.users.globalnet.co.uk/~walfor/simple.htm
The kit arrived within a day of ordering and then it sat on my work bench for some time while I plucked up the courage to take the soldering iron to it.

So many holes, so many components and so little radio knowledge!



Instructions are incredible, lots of detail and nice preamble just to set the scene for the build. PCB has no silk screen and this was a little daunting at first but the excellent instructions and component layout diagrams makes up for this.



First step was to setup the mechanical parts on the front panel.



Then tack solder the panels together. This was much harder than I expected and it didn`t look as clean as I was hoping at the end, but pretty solid and secure.



First step was to setup the voltage regulating part of the circuit and turn it all on and check voltages:



Then onto the output stage:



And finger/screwdriver buzz test:



Finger buzz test worked fine and voltages the same so it was OK to continue to the VFO and toroid winding!









and that is where I am up to so far. I haven`t got a frequency counter so I`m now a little stuck trying to tune in the VFO. Apparently for the 40m that I am trying to set this up for require a VFO freq count of between 5.0 - 4.8 MHz. I have just managed to get hold of a yupiteru mvt-7100 scanner and I can apparently use this instead of a counter....I just need to figure out how!

[SKIPRAT]

Hi There

I was somewhat amused by the title of your post  but nevermind you can probably guess from my signature that i practice in the black art of amateur radio. A 40 metre receiver interesting does that mean you have interest in getting liecenced or have you got one already . I used to do a bit of radio gear and electronic constuction a few years ago then the backyard engineering bug bit me i am still active on the 145 Mhz band and the 430 band and can be heard calling  "CQ CQ CQ  G6FOW " and hopefully getting replies anyhow have fun with radio .


Chers Paul

[Bluechip]

Chris

Nice one. Occasionally think about having a go myself again ... last one I made was a Maplin Regen Kit about 15 Yrs ago. Worked rather better than I expected    No end of fun fooling about with home-brew coils to find out where it could go...

'Course, as an old codger, I would rather you built a REAL set ....    

http://theradioboard.com/rb/viewtopic.php?t=2552

Dave BC

EDIT Actually, thinking about it, it must have been about 20 yrs. ago, been in this house 16, and it wern't here ..

[zeroaxe]

I ordered the Knole DC RX a couple of week back from http://www.users.globalnet.co.uk/~walfor/simple.htm

Completely off topic.... But imagine my surprise when I saw your link!? Cant believe Global(inter)net is still running!!!! Back then when I worked for Tech Support, they got bought out by an American  Company called "NextLink/Concentric" and then again later by "XO Communications"..... That was also the time when Freenetname got launched and shortly after "Waitrose Internet"........... I am still shocked that the free webspace is still up and running

[75Plus]

Chris, You need a little more heat to join those two boards. An 80 to 100 watt iron, just slid along the joint, should make it much stronger.

Using the scanner to determine the frequency is known as "Zero Beating". As you approach the set frequency you will hear a whistle which disappears when you are dead on and starts up again as you tune past it.

You may also be able pick up the US time signal station WWV. It is at exactly 5.0 MHZ and can be copied worldwide during the evenings when the bands stretch out.

Joe (n0fnf)

[raynerd]

SKIPRAT  , noticed the error and have now corrected it!

I`m having no luck with zero beating! I just can`t find a signal that resonates on the receiver I`m building. The instructions tell me the VFO should be at 4.8-5.0 MHz and so I tune my scanner to 5.0MHz, adjust the trimmer and just get nothing. Just the same dead background white noise. I have tried it at at 0.2MHz intervals from 4MHz to 6MHz and nothing. I guess the VFO part of my radio must be dead

[michvhf]

The VFO isn't necessarily dead.  When using a scanner as a signal generator you need to add the IF freq of the scanner to the freq you enter to get the freq you want.  Nope, that didn't make sense to me either.  Lets try this:  Your scanner has a 10.7MHz IF and your desired freq is 5.0MHz.   Tune the scanner to 15.7MHz and you should be good.   There's a pdf that explains what you can do with a scanner here:  http://home.mchsi.com/~mikevald/Scan.pdf   It's been so long since I've done it I had to look it up to make sure.

73 de KA8CSH   (Vince)

[Fred Bloggs]

Gents

Completely of topic other than the build brings back memories of when I was at school (late seventies). The school at the time had a linsenced "after school" radio club (G3UBG) staffed by several of the older teachers -all radio hams, one of which was the well known John Morris (G3ABG) who had set up "Worked all Britain" years earlier. All the hams were ex war time operators and some of the things we used to get up to as a bunch of 11 to 16 year old boys (& girl) would make the HSE's hair's stand on end today - "ours did quite oftern" - you soon learned from your mistakes. I remember us quite oftern driving onto the high spots on Cannock Chase and climbing trees under the supervision of the staff  to string 100 meters of copper up as an aerial, dragging 6 old lead acid batteries out of their own cars and setting up a mobile HF station,  what a great way to spend summer afternoons, scoffing chocolate and biscuits in the trees talking to half the world. no face book or mobiles in those days!!! it was a thrill to talk to some one in The US or Aussy.
John Morris retired in the summer of 1980 due to ill health and past away  soon afterwards (probably all the RF he was exposed to), we were the last group of kids he taught!!

The ramblings of a middle aged man with young kids

Fred

[shoey51]

keep goin mate VK4GBS listening dit da dit da dit da

[raynerd]

Cheers mate, it is now actually running - I was measuring the freq on my new counter and didn`t take account the capacitance in the wire so I was running at 15MHz instead of 14MHz. I`ll post up when it is complete. I`m currently working on a freq counter for it so I can display the receiving frequency on an LCD.

I also passed my Foundation so I`m just awaiting my call sign!