Using DDS with Bitx Version 3

The Radio Amateur's Hand Book

Om Inge from Norway is using DDS with his Bitx version 3.  Inge has been very kind in sharing his modification , and correct way to use DDS with Bitx Version 3. We will also publish these details on http://www.bitx20.com

Bitx20 and other Qrp projects

Cqbitx was started in 31st July 2000.   That is 10 years now.  We have contributed to the cause of Bitx and have never mentioned that Bitx has to do anything with our contribution towards the design.

We have helped more then 300 members with Bitx 3 Kit as by Ashhar Farhan and Mods by VU3WJM.

Infact from day one we have placed links and given correct info about the authors. Many Bitx version are in the making, we had started this blog to help Radio Amateurs to get kits for Bitx Version 3 as modified by VU3WJM.

In a hurry to publish our new website , we had un- intentionally  not mentioned the author, but had placed links to Bitx Forums and Sites. But we have corrected all the content as regards  to giving due credits to the Author and Contributors.

Bitx 20 name is very appealing as you can understand my sentiments, that I have worked day and night for 10 years promoting Bitx Kit and info world wide with many other kits too.
So by launching a website with Bitx20 domain does not mean that I am misleading or taking credits.

This is a free world and anyone can book a domain name if it is available, and since I am already working for Bitx, so its very easy to under stand why I like and booked Bitx20.com

I have an interest to promote many Kits and offer Hams world wide with Kits. I will also be booking new domains like for Bingo. Avala,etc etc. so does that mean I can not book these names as they are work done by others?
Infact I am making the projects more popular by dedicating my time,my money and efforts, those claiming that I did wrong in naming Btx20 should study all hard work for so many years by working days and nights to just help Ham community. If I spent this much of time on a lucrative business then I could have made many money spinning websites. But since I am a true Radio Amateur , helping hams appealed to  me as a good activity.

I am sorry for any inconvenience caused to parties that may be hurt, but is was a must to make my-self clear .

Best of 73's

Cq Bingo Launched

We have have corrected some issue with Bitx20 site and everything is in order as for mentioning the authors and contributors.

Its gives my great pleasure in informing my friends that I have launched a new blog site Cq Bingo.  http://cqbingo.blogspot.com .  You can view the blog , but its in early days, and lot of work has to be done.
We have all the PCB ready for Bingo so it want be a problem supporting friends with Bingo Pcb and Components and Case,

With best of 73's
de
vu3sua

Building Bitx 3 , by the BiTX20 building group at 147.120 Tech Net

If you  want to keep a track of building Bitx Version 3 with the way friends at the 147.120 Tech Net are doing. Then please do visit their blog and see how a group project is being build with club members with test equipments.
They have build the FLL Kit which was start of their project.  Here is the link
http://technet.147120.com/technet/?p=401

The second meeting was to take up Bitx Bandpass Filter. Here is the link to the building and measurement with test instruments.  http://technet.147120.com/technet/

I think the test equipments have not helped them decide the correct capacitor.  We have made many Bitx and found 39 Pf the best value. That has been tested  in practical receiving and transmitting.   Lets see what is the outcome for club in the next meet.

The error in print is regretted . The PCB shows 68Pf but we have advised for 39PF.

All the best friends

Bitx20 Launch

 The Bitx20 website has been launched after remaining unfinished for a long time. The website will give in more details and comprehensive info regarding Bitx version 3.

Rahul  VU3WJM is working on some mods which should make the Bitx version 3 much more better and the errors presently in documents or schematics should be done away it. We would add some extra features , which we will mention when we have incorporated them in the new pcb's.

Also soon we will put on sale  PCB for LSB/USB change,  Crystal Filter For SSB/CW,Band Pass and Low Pass Filter PCB.   We are waiting for TOKO coils so that we can give complete kits for Bandpass and Lowpass Filters.


New items will be placed on Bitx20 site  soon, so keep a watch on the site http://www.bitx20.com.
If you have any suggestions for the website then kindly do email your suggestions.

I would like to give a special thanks to all my friends who have visited bitx20 site and left their kind
comments in the guest book :)   Very much appreciated.

Best of 73s

Bitx Version 3 For 20 ,40 And 80 Mt Bands By Ross Bell VK3BEL

 

Bandpass Filter PCB

Low Pass Filter PCB And LSB /USB PCB

Our Australian friend Om Ross Bell VK3BEL is doing wonders with Bitx Version 3.

Ross likes keeping his Bitx simple and as original design, that is without a digital readout.

Ross has successfully made the Bitx for 3 Bands presently that are 20 and 40  and 80 Mt Bands, with modules provided by us for LSB/USB Change, which is a small pcb mounted above the Bitx Main Pcb BFO.

The second PCB is the Bandpass Filter, that is made for 2 Bands and additional PCB can be added for extra bands.
The third PCB is for the LPF also for 2 Bands.

We also have a PCB for using in Crystal Filter that can be used for Changing Filter For suitable use, ie CW.

We are publishing pictures and statement on Bitx  Version 3 for 3 Bands use as per Ross Bell.

Suggestions And Comments as per OM Ross Bell VK3BEL 

The bandpass coils were all wound with #39 wire on the same as the
20mtr coils supplied, a fiddly job.
for 40 mtrs 18 turns / 3 turns with the capacitance values being 82p
in parallel and 8.2p in series with the coils.
for 80 mtrs 21 turns / 4 turns with the capacitance values being 270p
in parallel and 22p in series with the coils.
For the VFO ,I multi tapped the tuning inductor for the required
2.7-3mhz ,4-4.5mhz and 6.2-6.5mhz,  75, 51 and about 28 turns for all
the bands.
To set up the bandpass filters, i connected them with coax to a
receiver and tuned the coils for maximum signal on the required bands,
only a small adjustment was needed after installing in the bitx.
It is great to have 3 bands, always a signal.....
great fun...
Thank you...


Hi,
I replaced all vfo caps with npo's , waxed the coils to the pcb and
also found the replacement of the zener with a 3 terminal regulator to
be much better frequency stability.I also placed a copper shield
around the vfo and the stability is good. I use the set all the time
and plan to go portable soon. all three bands are working well.

************************************************************************************

Well we thank Ross Bell for his Bitx Version 3 operating on three bands and wish Ross all the best for his Bitx version 3 for other bands too. :)  Cheers!

ALL DUE CREDIT TO OM TONY FROM UK FOR PROVIDING DESIGN FOR BITX ADD ON MODULES

Adjustments for S.Meter

     

Adjustments For S.Meter For Bitx  As sent by 

I0VBR Vittorio Bruni

1. Solder all components to PCB
2. Connect Potentiometer 470K to Audio in Bitx Volume Control. 10K
3. Disconnect Antenna to regulate the adjustment for Potentiometer 470K, to Zero for

least deviation of the needle of the meter. It needs to regulate to the position where the needle extends as soon as to move itself

Finally connect antenna and adjust 100K Pot to S9 on a strong signal of 50uv to the antenna entrance