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This is what happened to me with my first ?BitX; yellow volume wire was connected to volume wiper (Vol-M) & orange wire was connected to Vol. high, which is backwards. Once I corrected that, the

Kees, What is the difference between the 1.5 & 3in boards? Larger physical size makes it more effective? -- Mike AI4NS

All: I'm positive Hans said what the microcontroller was that controls his new QSX rig. While I'm pretty sure its an STM32, but I can't find which flavor or the post that (I thought?) mentioned it.

One more........ Inquiring minds want to know............ What is the power (or "sensitivity" level) of the AXICOM 12V relay relative to the others since there are typically 3 or 4 different power

Note that the addition of a 100uH choke in series with the coil improved the attenuation 10dB......but there is that self resonance peak. Don't know the effect (yet) of having a 100uH (or larger)

Those inductances all look right. Sure would like to know WHY the Axicom relays have better readings.? It just dawned on me that when I'm measuring all these little LPFs, whether I built them up or

Hope she's ok.? Sorta suddenly stopped posting.

Your values look to be in line with what I measured, Jim.? .02uH is 20 nH.? I only measured one of each brand. --Mike--

Hans will your upcoming transceiver kit have the option to add a TCXO oscillator??? -Justin N2TOH

Thanks Jim. That is quite promising. _._

How did you measure the inductance of the armature? I tried with my AADE LC meter and I get .02 to .028 microhenry on all 5 new relays. Not sure I'm using the right method to measure that particular

Kees, In measuring a Virtual relay and an Axicom relay that I have here, both show approximately 20nH.

Since we have AXICOM relays in the group now, can someone please measure the inductance from the N/C contact to the Armature on one of those relays. To see if it differs any from the 6 other relays I

Jim, I stand corrected on my CW comment since the uBITX is not QSK. Someone asked what adding a 100uH inductor in series with the coil does. This is the plot of the larger 16 pin HFD27 relay with the

Kees, and others. After much testing, re-designing, analysis, re-testing, etc. we seem to be slowly zeroing in on several ways to improve the situation regarding spurs, harmonics, etc. When this is

Are you saying that the second 45mhz mod can be removed from the TX with this mod? How much power loss is lost with the 45mhz is in place? Nice work by the way. I’d like to try this for sure. Joe PS

The through-hole 2n3904 uses a silicon die that is identical to the surfacemount MMBT3904. The through hole package can dissipate more power, but I believe the failure mode is excessive voltage

One other question. If I have replaced Q13 with a larger through hole version of the transistor, is the diode protection mod still required to protect that transistor?

That’s very good news! That will probably suffice for the vast majority of people.

Why would it bother the CW ops? The uBITX is NOT full QSK anyway and the relays do not follow keying. They remain energized for a short time after key-up before returning to RX. Jim - W0EB