Thursday, January 17, 2013

4 mistakes

Considering the sheer amount of connections and components I wasn't expecting 0 errors building the kit.... but from what I found so far none made were critical to the transceiver function. Here's the mistakes description:

* Frequency on the frequency counter: I was getting strange behavior from the frequency counter, the frequency was offset for some 500Khz, if it was by the IF frequency I could suspect on mixing effects or something, but 500Khz?... I finally thought it should be the code on the PIC, started to look around and guess what, the supposed 4Mhz clock crystal for the PIC was an 8Mhz one, how this happened I don't know but it's probable that an 8Mhz crystal came with the kit instead of the 4Mhz one. Replaced and now it's spot on.

* IF gain control: Was counterclockwise increasing, changed to "standard" settings.
* Drive power/RF output control: Was counterclockwise increasing, changed to "standard" settings.

* 40m bandpass filter: Not actually an error, it was working from the beginning but with marginal settings so will try to improve a little bit, anyhow can now listen to CT and EA stations with just 2m of wire connected to the "Speaky" antenna terminal inside the shack.

Now some photos on the "Speaky" parts:

40m band module:
Main board, frequency counter, band module, low pass filters:

Next steps:

* Finishing the 17m band module 

* Testing the first transmission

Have reception on the 17m band, have transmission audio and RF power but it was just a quick test, I have to tune all the transmission path settings first.

See you!

No comments: