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I got the ubitx with the problematic WX TDA 2822 Chip which on power up of the ubitx gave off smoke and got very hot. I removed the TDA 2822 chip and installed a socket. When I put in a new TDA 2822,

If you’re correct, that’s a great pic up. The input and output lines are probably the most crucial I would guess. What would you think about replacing just those two with coaxial cable Rg-174 type

Dennis, Color me confused, what issues would be fixed with a balanced line? Allison

Dexter, More than half....? the side with the bigger headaches.? :) Allison

You know, with some BAP64’s, you could switch these in and out very efficiently and the build with SMD parts would be very small… Sent: Saturday, August 4, 2018 4:08 PM To: [email protected]

It is interesting the long and winding road the RF takes through the relays for the filter switching. If that is a source of coupling for the harmonics, would it be possible to use this alternate

Ahh, yes...peak the grid, dip the final. The good old days... ;) Mark AA7TA

Warren That sounds like a simple fix. It possibly could be made with RF switching to select which filter is in use. Arv _._

Did it make the board any lighter, Allison? It certainly made the thread 'lighter'! :) 73 Dex, ZL2DEX

Why not look at using balanced line instead of coax? Seems many of the issues you are talking about disappear when balanced line is used.? -- 72 and God bless KD4EPG

I lifted a top side trace at the IRF510 and soldered a wire on the bottom side of the board between the existing solder points of the coil and final. You can back up on the traces and attach to the

Rahul, The LCL preselector is one I've tried.? The show stopper is the 500pf dual capacitor and the 4 switches.? Works as shown but bulky. That is also a three part and the third has an interesting

Warren: Can you post your scaled values for the 20m filter? Also, what voltage rating is appropriate for the caps? Thanks, James

Lol, there is still an AGC board hovering around the Chicago area between Chicago USPS and Chicago USPS Regional Facility Chicago IL International Distribution Center. Guess by now that package has

My external filters constructed with values from the article.

Tasa YU1LM has something of interest. http://yu1lm.qrpradio.com/BP%20FILTER%20HF-YU1LM.pdf Rahul VU3WJM

What about installing these https://www.qrp-labs.com/bpfkit.html?as switchable bandpass filters at the wiper of RV1? -- N5KBP

This page contains three simple filters that were used to augment the internal filters of the Softrocks RXTX which suffered similar harmonic issues. I have built all three filters plus one with scaled

A suitable one made by Bourns is available from Digi-Key. Their part# is PEC11R-4020F-S0012-ND and I've used these with my various uBITX radios since day 1. Not terribly expensive either, I believe

Can anyone give me a pointer on where I can purchase a replacement encoder for the Ubitx Thanks 73 art - n2ajo