Wednesday, October 3, 2012

BITX20 - 19. VFO..stupid stupid stupid....

Just a little quick post which will show again why you need a proper guide/manual to build stuff if you don't know what you are doing too well.....

Today i came home early and while driving home i was talking on the repeater of Zaandam, where all of a sudden PA1ED came on... as you might remember he is the one who got me started with the Bitx20 and is also the one i talk to if i need a proper translation from what Sunil writes in his guide, to something what I as a dutchie understand. The conversation started like this.....

Me: Hey Ed, guess what, my IK3OIL FLL VFO runs at 14 MHz !! Woohoo!!
PA1ED: Ohh then i think it's broke... what did you do with it?
Me: Huh? What are you talking about??...
PA1ED: Well , unless you wanna end up at 24MHz, the VFO should not run at 14, but at 4 MHz....

Then as he said this , it hit me....the BFO runs just under 10 MHz... and you need to add that to the frequency of the VFO what will end up to be the frequency you use....
This was what Ed explained quickly as well as i was nearly at home..... So back to the drawing board ....

I will get there though.... just happy to have people correct me right in time before i really blow up things!
So again a big thanks to Ed! :)

73's

Alex

A new toy in the shack! A PM3055 scope

I have been wanting a scope for a while now, but i did not want to buy a new one or a expensive 2nd hand....
So i have been keeping eye on thge dutch eBay called "marktplaats" where all of a sudden i noticed an advert for an Philips (Fluke) PM3055....which was an expensive one back in the days :)

Now the 3055 came in 2 editions.... the 50MHz, and a 60Mhz.... As this one was a 50 MHZ i was a bit reluctant to buy this one. But the seller stated that the scope was good (yeah they all say this) but that it included original 2 probes and that both the user manual AND the service manual were included.

After some research i quickly found that these scopes have problems with their power supplies... but also the fix... Just replace all axial capacitors and ur good to go....

So after 1.5 hours driving there, and 1.5 hours driving back..... this is the new edition to the shack !


Next will be an LCR or an ESR meter ... not sure yet..... sugestions are welcome!

73's

Alex
PA1SBM

Tuesday, October 2, 2012

BITX20 - 18. VFO at 14 MHz....

Last Saturday i got my potentiometers which i ordered. WOW fast delivery this time from China. Just 6 weekdays. So needles to say I started to work on the VFO again.

The strange thing I had is that my VFO was at around 12 MHz. Which of course is too low :)
The only thing I could think off was the toroid I had wound to be wrong. After checking it turned out to be according to what IK3OIL writes in his building instructions......
Well almost.... it says to use 0.5mm diameter wire... which i did not have , so i used something slightly thicker... well twice as thick.....

As the instructions show that if you use less windings , the frquency will go up , i started to remove one winding at a time.... And i got it to get to 14 MHz!!
But as i had to remove too many windings to my liking, i decided to get me some 0.5 wire.
So that's now ordered, and as the eBay wrote me yesterday, sent allready as well :)

I checked all other components as well and I noticed that IK3OIL thinks that C8 needed to be 60pf ceramic, so as Saturday is a ham parts fair again , I will look for that as well.
I'm not really sure why this is though... the normal trimmer I used seemed to work OK.

I hope this all will "solve" my "problem" :)

Will keep you all posted... until the next post!

Alex
PA1SBM