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Ok.???? Guess I am a bit long in the too but i grew up with 4 band coding......the last being tolerance.? These resistors are five bands hence the error on my part.? Also the first two bands

You means spectral purity around the fundamental or the harmonics? Listening to a few hams on VHF, having an SDR receiver, my impression is that around the fundamental they were not very clean. I have

Hiro, I would think with 3 or 4 Nano's you would have one without the objectionable tone. The processor clock frequency is determined by a 16mhz ceramic resonator which can be off by perhaps plus or

Many thanks, Jerry. It seems that my issues is the same one discussed at the thread you pointed out. I happeningly ordered some extra Arduino Nano for my another projects, so let me try to switch

Hi, I wan't to build a filter I can use with the uBITX. However, I don't want to build a filter that is strictly tied to the uBITX.? So I'm building a standalone Low Pass Filter box that will work

I barely know how to do this, but I uploaded the design document, and the zipped gerber files (which pcbway.com was happy with) to this github

Here's an old thread about audio tones in the receiver, possibly due to beat notes between harmonics of the 12mhz bfo and the 16mhz Nano processor clock. ?

?Hi Jim, Allison already did that for a motley crew of raidos, including a Heathkit HW-100 and they all were good to go except I think one reallly clunky design. The general thing was that most

Put decent RF devices in uBitx and then we compare for sure... Rahul VU3WJM

Hey, I'm just curious how all the other portable radio compare.... Are they :"clean"? Specs can be that "special" radio, just for testing. Your mileage may vary, Jim W0CHL

I bit the bullet and submitted files to pcbway, for 10 printed circuit boards for external relays. While I was at it, I threw on a small bit of circuitry to give me a 3 terminal regulator and a

?Keyes (1) OK, good that you have a ground plane image that handles the ground connections to the relays. (2) you might consider taking some action to avoid blow-around via the coils.....Allison

all due respect Allison Bitx20A is a dual IRF510/A? class B? design with substantial drive frm small signal drivers . I is suppose to produce 12W clean if well set up. Basically the parameters are

Though it took a little longer time, finally my uBitX seems to be working very well now, for which thank you for advices here so far. Then, another question to ask you who experienced the same

Gordon, The ground pins on the filter trays are connected to the ground plane on the board and there are 3 grounds and the coax shields which return to uBITX ground. I'll also send the ground plane

For some reason the PDFs were duplicated so I erased the thing and redid the note.....confusing enough ;o)? PRELIMINARY.............. The idea here is to use the existing uBITX components on a

?Hi Keyes --- I wasn't following so not sure if this is for OUTPUT or as a preselector for the PA stage. I don't know exactly how to read your PCB's but a few questions: 1. I don't see the ground

Pretty picture nothing else, looks slick and tiny.? A schematic might be useful. Allison

K4MRT, I sincerely doubt you getting 24W (70V-PP).? I can believe 7W. Into? a 50ohm load I'd expect to see maybe 35VPP. for around 6-7W. Most people put a scope probe across? the output and and

The non push pull bitx amp is class AB1 (around 50 ma bias) single ended. The power out is more a function of the drive available and they tended to be all over the map.? With 200-400mW of drive the