Tuesday, December 25, 2012

Happy holidays !!!

Hello all !!!

Even at christmas i have no time for myself.... (not complaining though... this is an awesome time)
We travelled down to my parents and we are spending the holidays at their place.
So inbetween the starter and the main course i am blogging to all you out there.


We ( Alex, PA1SBM, en GF) wish all people reading my blog the best Xmas ever, and for the new year all the best DX and lots of succesfull homebrew projects!!

Merry christmas and a happy new year !!!


p.s. i hope to get some time soon for the Bitx20 so keep an eye on my blog or twitter !!

73's 

Alex
PA1SBM

Sunday, November 25, 2012

4 meters / 70 MHz 1/2 wave antenna.

For a long while i own a Ascom SE550... And i installed it in my shack, and it has been happilly hanging under a shelf next to my Kenwood TM-733e....


Well it was not that happy i think.. reason be the lack of an antenna....

I did not want to just walk in the store and buy one because i like to build antenna's to see if i can make something as good as a "professional" supplier. So i started to search for a design on internet and found....
http://www.70mhz.org/halfwav.htm   by by Ross Wilkinson G6GVI .

So i started to build one , but i could not seem to get it just right.... I could not get it to a SWR under 1:2.
Nothing els left to do then walk over to my neighbour (also a ham amateur) and tell him he would be without his mfj antenna analyser for the next few days.
Now this is never a problem, so i hooked up the MFJ and started to find a sweet spot for the coil, and experimented with different trimmers. Until i hit something which was good enough for me...




After getting to this... and yes i know it is not 1:1 and it is not 50 Ohm... but sufficient for what i want to do with it.
The guts of it look like this......

 
 
 
The door it is in front of is the entrance to my shack :)
Ok, this smal project is done, now back to focussing on my Bitx20!!

73's
Alex
PA1SBM







Saturday, November 24, 2012

Busy,busy, busy,busy, aaarrrrgggghhhhh

Hello all....

I think the title of this post says it all.......

Lately my work has grasped all of my free time. doing 6 days a week , 10+ hours a day..... 3 to 4 hours commute.... Well you can imagine that this sucks all the energy you have out of you... if you can't... let me assure you , it does.

As some of you all have already gotten in touch with me if i plan to finish the Bitx soon... Let me assure you i have no intention to finish it tomorrow, but i do intend to continue in a steady pace...
It is allready annoying me i did not spend any time at it for the last 2 months.

In the mean time i did finish an antenna (quick project) which i will write about soon.

Keep posted... more new posts are on the way!

73's

Alex
PA1SBM

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

Sunday, September 23, 2012

BITX20 - 17. VFO first test....

Yesterday we had the "ROM" at "the lichtmis" Dutch amateurs will know what i am talking about, but as i have a lot of people and fellow ham's following me from abroad (which I'm really proud of, and thankful for) I'll explain what this is..... It's a small radio parts meeting. which has become a "must go to" for most hams in the Netherlands. Even though it's in the north part of the Netherlands, i always hear people from down south as well... This market is without a doubt one of the most fun markets to go to.

Well, anyway, i bought some parts which i still needed for the VFO. uhmm well, i only needed a 2k multiturn potentiometer (variable resistor)(blue thing in the picture)
This morning i started to hook up everything to see if it would work.... and it did....
For calibrating i need a 10k potmeter as we call it in the netherlands :) and i dont have any...
That's why you don't see a 14 MHz on the display yet. the vco is not hooked up yet
I'll be placing an order on eBay shortly after this post :)


Again i am getting a step closer to a working bitx, but there is still al bit to go... s-meter, agc...
But i think after the winter I'll be qrv on this set :)

UPDATE: potentiometers ordered :)

Saturday, September 15, 2012

BITX20 - 16. Building the external vfo part 2

Ok, finally i got most parts now.... thanks to ebay :) ... i ordered about 1200 capacitors, and the transistors i had a problem with getting where i live, the 2N2369.

A HAM friend of mine provided me with the 2 trim capacitors. which were the last parts needed to fill up the PCB.





Next problem will be the 2k multi turn potentimeter, but there is a HAM fair next weekend again :)
And if i have no luck , another one 2 weeks after that. So i guess this will be easy.

When this is working, I'll start to put the bitx20 together , cause the last part is the PA part, which seems not that time intensive. so maybe this year it will be done. (Remember i never was in a hurry to build this :) )

Sunday, August 26, 2012

Redoing the shack.

Redoing the shack..... Well this is not really true...
My shack was close to what people describe when you talk about world chaos....
Lack of storage and time.... and me just dont feeling like doing anything about it, let to an awfull WW3 scenario which i can't even describe anyway....

So as in the beginning of this month was my birthday , i asked my parents to get me storage cases for components. And i got 2 even... and i bought 1 to go along with it.

So now i had no reason anymore to keep postponing the shack.... well.... i did last weekend.... outside temperature of 35c to 37c which causes it to be around 42c in my shack...
So today i started to make sure i would have a presentable shack....
Its not done yet, but the start is here :)




The 3 big ones are the new ones. the 2 on the left have resistors in them, capacitors in the right one.

73's
Alex
PA1SBM

Sunday, May 20, 2012

Links on my blog....

When i started this blog, i already noticed that i got hits from other HAM's blogs and sites...
I think the links on each page pointing out other interesting blog's/site's is a great thing.

So i now try to put more effort in getting on people's link pages, and i try to add as much useful links to other people on my links page.
If you want to be mentioned on my link page, please let me know by dropping me an email,comment, or any other message, and i'll add you as soon as i can...

Cheers!

73's
Alex
PA1SBM

BITX20 - 15. Building the external vfo

I ordered my bitx20 including the LCD frequency counter option.
At that point Sunil included a pcb for a vfo that works together with the frequency counter.

So i started to build this. As no components were included, you have to gather all parts yourself.
My component stock is no where near big , but with the basic stock i have, it almost filled the complete PCB


The components that i am missing are not uncommon ..... i think....
Just som capacitors, 1 coil, variable capacitors, diodes, etc....
So whe i am going to a small hamfair upcomming saturday, i hope to get al parts i need.
If not i still have some ham friends, or online suppliers that can supply me with the parts needed.

Saturday, April 14, 2012

BITX20 - 14. The exciter is finished !

I had to make this a separate blog post.....
but the exciter is finally done....

Here it is :)


Now on to the PA part... yeah more coils :|

BITX20 - 13. The output driver

The output driver section was not hard.... even with the coil to be wound...
It was a bifilar, not a trifilar.... so that made it slightly less annoying :)

as this is near the end, i now noticed i am missing a few more things....missing a 100 Ohm and a 1k Ohm resistor. No Clue what i am gonna miss next :)
This for me is one of the charming things of the Indian package. Now if i paid the qrpkits.com price, i would probably mail them for every single item i missed. Now i just took them from my own stock.


As you can see... it is just a small part...

Measurments came out fine, so no worries there!

Friday, April 13, 2012

BITX20 - 12. Xtal section...

Ok , this was hardly any work.... 4 xtal's and 3 capacitors....
No measuring either....


Now there is only 1 section left on the exciter... the output driver.... with a dreaded trifilar coil @#$@#
No time left now to make it. maybe late tonight....

BITX20 - 11. Audio section completed

This was easy until i noticed that i was missing some parts.... I missed a 1uF capacitor, and i noticed i had a 10uF in my capacitors bag. I have done some reading in the part lists in the manual , but i think thy misplaced a 1 by a 10 uf capacitor... As any DIY person should, i took a 1uF from my own stock, and put it in.
The same happened for a .001 uF capacitor... again ... $100 including shipment... i am not complaining.


The only thing weird is that my Q10 measurements are a bit too much off for my liking so i will check those with PA1ED (yes he got his full license now!) and see what his measured value's were.
As they are not way off, I'll continue for now.

On to the XTAL section !

Edit:
Note:
For those who wonder why i now all of a sudden build a lot compared to the usual slow pace....
I treated myself to a few days off... :)

BITX20 - 10. BFO / Modulation section done.

ARRGHHH i was tricked.... well i just did not read stuff good enough...
There were 2 coils... one not that bad, but the other was the 3rd dreaded trifilar coil....
And i know that for the exciter board i still have to make one. (and 2 i believe for the PA)

Anyway , the rest of the build was fast and painless.... (except for the manual saying 50uF, and them supplying 47uF) (also a normal fitting potentio meter would have been nice)
So lets not complain :)


Measuring all showed me no weird things... Just the normal difference... measurments just never seem to be exact :)

Audio section is next.... And now i checked the list... no coils :)

Thursday, April 12, 2012

BITX20 - 9. Building and meassuring the 2nd IF Amplifier

Oh how much joy building none coil parts :)......
So the 2nd IP Amplifier was done in no time..... and i enjoyed it a lot!


Does any1 notice the 1 resistor being a different color ????
Yes indeed , 1 resistor was not included in the complete package. a 4.7 Ohm resistor.
Luckily i had one in stock.

Measuring this part was fun as well.....
There is a Q3 and a Q3a transistor.... and in the manual they have mixed up the value's what you should measure. So this again is one of the quirks from the BITX20 kit.
So if it says Q3, read Q3a , and if it says Q3a, read Q3..... And remember that this is a $100 kit :)

On to the next part !!! (still has no coils ;) )

BITX20 - 8. Building the 1st IF amplifier

After finally having done the trifilar coils, i felt like building more :).
So i builded the 1st IF Amp as well last night. It's all very straight forward.
I do not expect any problems here. This is how it looks......


Again you can see that the transistors are "the wrong way around" to the masking on the print itself....
This is still due to the change of transistor type Sunil has put in his kits. From what i have read on his blog, the new v3 kits should have a proper masking again, but i am not sure.
I intend to do all the measuring after i get myself another cup of tea.... Luckily the whole test setup from last night is still on my desk , so i can start straight away. I do not expect anything weird here so probably the next post will be on building the post if part....

BITX20 - 7. Building and measuring the "First Mixer"

This is by far the most dreaded part for me.... I don't know why, but i just do not like to wind coils.....
So that is the reason i have been putting it off for so long.... But! i forced myself to do it and.....


TAADAAA!!!!
There are the 1st two trifilar coils. Thank god that was done. Putting in the 4 1n4148 diodes was easy , so now this very small section looks like this....


After this we finally could measure voltages on the last transistor of the vfo part, and that turned out fine.
On to the next part !!!

Monday, January 30, 2012

BITX20 - 6. Measuring the VFO

Just a small progress update on the BITX.....
A while back i build the vfo part and started to do all the measuring as discribed in the manual....
Unfortunately the value's described in the manual is no where near what it should be....
So i emailed an other ham operator who has build 2 already to see if my value's rang a bell....
And they did :) thanks PD1ED.

I am sure other people will have the same experience... So i will share this info as well.
Or, if you are into yahoo groups, do join the BITX20 group there. It's a real goos source of info.

Current drain, 34,8mA, not 44,4mA

Q5:
E: 7.21v 4.76v
B: 6.96v 4.87v
C: 8.48v 9.88v

Q6

E: 6.36v 3.99v
B: 7.08v 4.66v
C: 8.48v 9.89v

You can see how much the difference is and then, if not told you will start to worry like me.
(These are my measurements, please remember that they can differ to yours as components, testleads and multimeter's have various deviations)

Well , next weekend on to making transformers....

73's
Alex

Sunday, January 29, 2012

A new toy in the shack.. a TS-440 SAT

A few days ago i managed to get my hands on a set which i wanted for quite a while....
Even though i have a "Mobile" TS-480" i wanted a 2nd set just for field days.
The TS-480 is still scratch less and i did not want to make it look used.... So every time we went for a field day the 480 was put in a little case with loads of cloth. You can imaging that this is not an ideal situation.

So i finally bought a TS-440 (obviously 2nd/3rd/4th hand).... Its in very good condition if you keep in mind that this set at newest is 16 yrs old. (at least , i think they stopped producing it in 1996 like the R5000)
The person who sold it unfortunately smoked like a continues chimney together with the whole family, but he sold it for someone else who was a non smoker so the set is not clutterd with nicotine and tar residue.
He was also not really technical and had no idea if it had a tuner. (i wonder if he knows what a tuner is)
As i use a zs6bkw antenna in the field, i do need a tuner....
So i took a gamble and i drove to the other side of the country..... about 100 minutes in the car for a one way trip. And here it is !



And... to be honest, it sounds great.... there is just something with older analogue equipment compared to newer digital stuff.

As the seller was not really the most intelligent person i ever met (not saying he was dumb , just not educated in the HAM stuff) he had no idea what to anser my questions.... i did not bother and bought the set anyway...
So to get my answers... a) any filters inside b) do i still need an IF-10 set ic's for computer control... i opend up the set this morning..... And yes , it has the 2.4 ssb filter installed, no CW though.... and when i opend up the display cover i notices that the 2 extra ic's were allready there ! Sometimes i am lucky... mostly not though :)

So you might wonder is there is some negative thing? Yes there is... one thing is that it has keybounce on the band change buttons... but its minimal... second is that the powercord is SHORT :). so i have to fix that befor the field days :)