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And....the modified design would no longer be a BITX. There are other low power designs out there in kit or homebrewed form that would be much easier to modify for FM and/or AM.

I hope you are testing with a dummy load. The bitx20/40 doesn't like reactive loads. - f

I have a box full of speakers from a sale. All of them work.

For AM you would have to derate the power output from the ubitx to about 2 watts on 80m. 2 watts on 80m would translate to about 250mw on 10m. Is that enough output for what you want? Even narrow-band

You can't just connect D4 and D5 to the SDA/SCL leads. You need an I2C adapter added to the back of the lcd. this is an example:

Is there going to be a nice Hi Res picture of the Ver 4 board any time soon? I would love to see what it looks like. Joel N6ALT

Oscillation still occurs intermittently. mostly at an output of 3W or higher. There are a few RF leads where I could use short pieces of RG-174 coax cable. Is it best not to connect the shielding to

I'd expect a 16 ohm load to be fine. And if you were to blow it out somehow (I doubt it), it's a couple $0.02 2n3904's that you will need to replace. Jerry

Back when I was in high school my dad had an acquaintance who happened to be a ham, getting up in age.? In addition to a couple dozen 810 transmitting triodes and an appropriate plate transformer,

Arch there is no consistency in this Amateur Github stuff. Some builds like the kd8cec only worked once under Ubuntu but do on my iMac. Now its the other way arround Allards build is not working on

It is the audio amp in the Ver 4 board, Q72/Q73, Q71 in the following: http://www.hfsignals.com/wp-content/uploads/2017/12/ubitxr4.pdf Basically it looks like a little push/pull class AB amp

Thanks Jack! I tried to replicate but I keep running into the same error. The file format and structure for Arduino should be the same across all platforms. Going to fire-up a roadkill linux machine

HFsigs gets it from a chinese manufacturer called WTL Crystals. They produce it for us. Unfortunately, the minimum quantity is 2000 pieces. We are assured that they will keep producing them as long as

The TDA2822 audio IC was originally used in portable devices designed to use 32 ohm headphones so a 16 ohm speaker would be a better choice than an 8 ohm and much better than a 4 ohm. The higher the

Hi Jerry, I have 'some old gear' made once upon a time (1950s). I usually operate at reduced power and I also have added filtering to get the output cleaner just to be sure. This is not a *new*

We getl

There are lots of small audio amplifier boards from China on ebay tht you could use just to drive an internal speaker. Here is one example

I don't have much experience around RF design. So take my opinion with a large grain of salt. But here goes anyways. On 15 meters, the spur is only 3mhz away:? 45mhz-21mhz= 24mhz That's a fairly of

My micro Bitx arrived yesterday!? I'm checking to see if it has the new discreet transistor audio amp now.? I want to have some small onboard speaker in whatever box I plan that will work whenever

I put one of my Rigol spectrum analyzers on my uBITx this weekend before traveling and i can report pretty much the same as everyone else has seen. ?Im particularly interested in the performance on