Our friend Rogier and I are involved in an East Coast -- West Coast uBITX launch project -- we plan to assemble our uBITXs together (more or less, via Skype) and then get them on the air.
As has been my recent practice, I have opted to put my uBITX in the same kind of wooden box that I used for my three scratch-built BITX projects. See above.
Now, due to Farhan's wizardry the uBITX is considerably smaller than the box. This is, of course, a good thing. It leaves room in the box for many bells and whistles.
But here is my first box design question
Should I put the uBITX board to the front of the box so that the LCD can be connected to the board DIRECTLY via the connector on the Raduino board (no jumpers needed), or should I put the uBITX board to the back of the box so that I can stick the PA heat sinks out the back? In the later case I'd have to use 4 inch jumper cables to connect the LCD to the Raduino. This use of jumpers seems to increase the possibility of noise from the display.
What say the Knack Wizards? Back of the box with LCD jumpers, or front of the box with no jumpers but heat sinks inside the box?
Posts
You can test without a permanent install the noise with the jumper wires versus the plug in. Noise is the least of the problems that you might experience.
ReplyDeleteMine is remote but I am using a metal box for the install.
73's
Pete
If you are keeping the original heat sinks and inside the box I’d keep the LCD connected and move to the front. Use the back space for maybe an antenna tuner. Or maybe a LiPo battery. How about a digital mode computer interface?
ReplyDeleteI can’t leave things well enough alone so I’d make space for more whistles.
Jim
wa7hrg
My LCD display (20x4) will remain connected to Raduion and bolt to front panel of the metal box (Jameco Valuepro SY0207-R Metal Case 7.5" x 9.8" x 3.2") with plastic stand-off screws.
ReplyDeleteI want plenty of clearance from the rear panel for electrical isolation and heat dissipation. I'm even thinking of adding a small switchable fan (depending on it's noise level) since the PA's can be boosted with a higher voltage source.
73
Brian
Bill
DeleteYou might get away with acceptable noise using the stock LCD, but if you move to a TFT color display as I did, that interface runs at a much higher rate and is definitely a potential noise problem. I used a cabinet that is almost perfect for front-to-back spacing. I'm using a 2.8" color display with a transition board between the Raduino and the display. You can see it here:
http://www.w3jdr.com
Joe
W3JDR
The place where most of the "noise" is received is , the antenna. If the antenna into the radio is shielded, the noise has to make it to whatever unshielded parts of the antenna are available. The most sensitive parts are probably a good distance from the radio. That said, I think its good practice to shield the inner radio components, such as the synthesizer , from the outside world. Although were not worrying much about "type acceptance", shielding the internal VFO from the outside world is a great idea. Some are doing that with tape, others with metal boxes. Most are doing it. Even the guys with the printed out boxes are using some sort of metallic tape. Playlist with most box types : https://www.youtube.com/watch?v=NrnhZtPM5Bs&list=PLxzZgQElG0cG42aa1vcZIKjSWajlsO9gI
ReplyDelete