On Jun 22, 2018, at 8:53 PM, Mark M <junquemaile@...> wrote:

I had fitting issues as well. First off I used the short standoffs to mount the board (doh!) so it was WAY off. One I figured out it needed the longer standoffs it was about 2mm off side-to-side. I used a small round file to elongate the holes by about that much to the right (as you look at it from the front) and it fits OK now.

My main complaint is that some of the components aren't real high quality (mainly the phone jacks and the power connector). The on/off switch doesn't work.

All in all, I can't complain too much. A blank box from other suppliers would be $20-$25 and you'd have to supply your own connectors, hardware, etc, plus have to drill], paint, & label it.

As always, YMMV...

Mark AA7TA

On 6/22/18 3:58 PM, Ken Held KF7DUR via Groups.Io wrote:
I paid extra for DHL and the case took less then 6 weeks to arrive.
Has anyone else had a problem with the LCD display not fitting properly in the front cutout. Mine is way off, the LCD would need to move up and to the right (by one pin) for a proper fit.
I'm not very impressed with this case.
_._,_._,_

Forgot to put the link.

http://www.arrl.org/files/file/Technology/tis/info/pdf/8809017.pdf

 

 

If all I need is to use the ubitx as a 28Mhz IF for a 2m transverter
then all I need is a 28mhz high-pass, correct?

I would think that it would be easy enough to build a high-pass in order
to kill the 16mhz-17mhz spur. Perhaps build it into the transverter
itself.

Any recommendations?

Table two of the arrl.org filter reference shows that the 21 mhz bandpass filter 
has 15db of attenuation at 28mhz, that's 7mhz away.
We need something like 20 dB of attenuation at 2mhz away.
As Allison says, that's a tough nut to crack.

And I have my doubts about the filter I pointed to.

Jerry

On Fri, Jun 22, 2018 at 04:31 pm, Gordon Gibby wrote:

Forgot to put the link.

http://www.arrl.org/files/file/Technology/tis/info/pdf/8809017.pdf

 

 

I have just built a uBITX with standard components (no SMD's) from scratch on a PCB I designed - it works well. I have now designed another PCB which incorporates the Arduino NANO and the the Si5351 shield and I'm just waiting for the PCB's to arrive and then I will start assembling. I made some changes to the circuit to allow for a dynamic microphone and the use of screened TOKO cols for the 30MHz lowpass filter, I also changed the coupling arrangement to the 45MHz filter.

I have attached a picture of the original PCB and a PDF of the new layout incorporating the Arduino and Si5351

Maybe one day I will play with SMT but for now standard components are still easily available !

73's - Peter M0HYT

I am not sure if 28 mhz is a problem. I am travelling so I will go back and check. I switched to 4 filters to be fcc compliant from 3.5 mhz to 28 mhz. 

 

I have been thinking about using a common heat sink for the RF power transistors, insulated with mica washers of course and insulated mounting hardware. Would there be inter capacitance issues or some other anomaly. Any thoughts or experience based 
observations?

Summary:  All is well, unless you have a WX branded TDA2822.


Here's an old post regarding the TDA2822, many other posts in that thread worth browsing:
    https://groups.io/g/BITX20/message/43342

Yes, the TDA2822D is still available from ST, would be a good choice
if you don't mind the 50 mil pin spacing.   I'd stick with the NJM2073.

You missed my point Jerry. I am not suggesting 2822D. Please see
the spec sheet I attached. It is a lower power version of tda2822.

I think that die is being repackaged as TDA2822 in 8 pin DIP. It cannot
take the load and blows up.

But I'm just guessing.
Could be proven wrong.