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Allison: So, then, are bandpass filters the only option? Are there in-band spurs? David A Posthuma, WD8PUO Sent: Wednesday, August 22, 2018 5:46 PM To: [email protected] Subject: Re: [BITX20]

Jerry, I'm still a little confused. When measuring the voltage on the gate for example, am I putting one end on the power input and one on the gate pin of the final? Sorry for such a noobish question.

Do you see 12v on the tabs of the two IRF510's? You don't have to key the transmitter to see this, just have the receiver running. When you key the transmitter, the IRF510 gates rise up from ground to

Sorry if the last bit of the previous post was phrased oddly. I have connected the brown wire on the power in to the red one, so I am getting 12v to the finals. I now have 12v between pins 1 and 2 as

Iz oos, Its rare that distortion is heard on frequency. Is the guy 3khz up or down from you that would like to not hear you and you sputter and splatter. So with the good radio listen to your audio

Ok I may be onto something. I removed the DC connector and opted for Anderson Power Poles for battery power usage. I did not do the proper research apparently (took 5 seconds to look at the wireup).

David, ?Will low-pass filters not correct the spurs generated as well as harmonics? Thanks for sharing your wisdom. No.? Often the spurs are below the cutoff of a low pass frequency , they are low

Yes ...Since the relays at input and output are released and need be operated to tie to final/antenna, I just tack soldered some short pigtails to SMB connectors thence to TR502/7L13 Jim

Do a thorough visual inspection of the power amp, everything from Q90 out to the antenna jack. Including the antenna jack. The toroids and hand wound and installed by hand. A bad solder job due to

I would not just randomly replace stuff. You have dozens of parts to suspect. And it worked when shipped. Do you have 12v applied to the IRF510's when transmitting? You should see 12v to ground on the

Jerry, thanks for the response! I have an Icom 740, which is unable to tune to 11.997 HMz, but I am able to pick up the CW tone transmitted from the ubitx when tuned to the same frequency. Good news!

Since you can hear the sidetone, you have U1 working. Some people have had trouble with the center pin of a coax BNC connector not connecting well with the BNC socket provided with the kit.? ? Maybe

Kees, In no way am I questioning the strategies you and the team are working through. But can you educate me as to why uBitx doesn’t just use programming to simply select the appropriate

Iz The primary problem caused by high IMD is splatter outside the bandpass of the sideband filter. This shows up on the opposite sideband and on the high (audio) frequency side of the desired

Hi Darren, VE3XLT Can you make this correction to? CEC 1.097 Nextion screen for my basic 3.5" display? TA2FU Alper

I greatly appreciate your efforts and that of the rest of the team. David A Posthuma, WD8PUO 1 (616) 283-7703 Sent: Wednesday, August 22, 2018 3:01 PM To: [email protected] Subject: Re: [BITX20]

Hi all, I'm somewhat new but I've spent a lot of time looking on these forums for a solution to my issue. As a disclaimer, I started this project knowing almost nothing about electronics, save ohms

Jim, it sounded strange to me as well. But most qrps have just a final transistor and all the harmonics have to be filtered out. In the uBitx the push pull configuration of the PA attenuates the even

Hi Jack, Yes, most programing optimization is in the design and the chosen solutions to the problem you are trying to solve. That is a bigger picture than the smaller optimizations that the complier

Warren, you did quantitative tests that surprise me to a certain extent. Surely the uBitx is not an IC-7300. Even my SWL ears find the IC-7300 transmitted audio one of the best ever. But as I