开云体育

Date
Re: Has anyone received a zBitx?
HI Jim -- this has been explained in recent messaging. Take a read and you'll learn everything you are asking. 73 KX4Z gmail.com@groups.io> wrote:
By Gordon Gibby KX4Z · #115971 ·
Has anyone received a zBitx?
Hey everyone, Since we're at the end of February.? Just wondering if anyone received their zBitx yet.? any reviews etc.? If not is there a date when they will be shipped/Delivered and available
By Jim · #115970 ·
Re: Looking for the V2 Hardware Upgrade Info
I misunderstood you, I thought this was what you was searching for. Swing and a miss I guess. Haha David w9jes.com@groups.io> wrote:
By WK4DS · #115969 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
As shown in the scope image, I have ca 4.5V peak-to-peak there when transmitting.
By WZab - SP5DAA · #115968 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
Is it possible that the software got crazy and didn't enable any section in the LPF filter? 73, Wojtek
By WZab - SP5DAA · #115967 ·
Re: uBITX v6 Low Audio - Back at it again
If after de-soldering of C30 voltages on Q30 will be near voltages of Q10, so: E= 1.6, B= 2.4, C= 7.9 Then You need to replace C30 with any 100nF (0,1uF) ceramic capacitor. If voltages will be still
By tomekdm sp7etd · #115966 ·
Re: uBITX v6 Low Audio - Back at it again
Hi Richard, Really sorry, my mistake, I have measured C10 again to the ground and this is also ~823 ohm. But don't bother with C10, nor C30. This is the same as measuring resistance from base of Q10
By tomekdm sp7etd · #115965 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
Wojtek, the scope photos were very helpful. That transformer is supposed to Step UP the voltage, not down.? ?So something is terribly wrong, and it appears tht bothof your FETs are doing fine. You
By Gordon Gibby KX4Z · #115964 ·
Re: Looking for the V2 Hardware Upgrade Info
This is from Farhan re upgrading my V2, "The standing current in the diodes that switch the LPFs was found insufficient on 3.5 MHz, hence, the resistors R201, R202, R203 and R204 are changed from 470
By Joel Caulkins/N6ALT · #115963 ·
Re: Looking for the V2 Hardware Upgrade Info
Joel, FYI, changing the resistors increased the bias current on the PIN diodes for the LPF and T/R switching diodes.? This was to reduce spurs and improve power output, 73 Evan AC9TU
By Evan Hand · #115962 ·
Re: Looking for the V2 Hardware Upgrade Info
One of the things to change is R201-R204 to 330ohm 1/4 resistors, I remember doing mine but I don't remember why, other than that I don't recall doing anything else. Joel N6ALT
By Joel Caulkins/N6ALT · #115961 ·
Re: uBITX v6 Low Audio - Back at it again
Before I stat removing components, I'll report the following based on your last suggestions: Resistance from base of Q30 to GND = 50.8 ohms, no where close to 836 ohms. Resistance from base of Q10
By Richard AG5M · #115960 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
pt., 28 lut 2025 o 20:38 Evan Hand via groups.io <elhandjr= gmail.com@groups.io> napisa?(a): As shown in the scope images, the DC of the drain voltages remain at ca 12V. It was the DC multimeter
By WZab - SP5DAA · #115959 ·
Re: Looking for the V2 Hardware Upgrade Info
JJ, I do not have the documentation; I have only the GitHub files with the original V2 schematic. The zip file is attached. 73 Evan AC9TU
By Evan Hand · #115958 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
Wojtek, Is your power supply voltage dropping?? Strangely, the drain voltages drop when you key the mic.? This could suggest that T7 has an issue.? Confirm that you are seeing the drain voltage
By Evan Hand · #115957 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
Do you have 1V here when you transmit?
By sa7buj@... · #115956 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
I have checked signals with the scope (measured with 1:10 probe with DC coupling, 500 mv/div so 5V/div considering probe). Ground level: DC level on drains of finals without RF: Voltage with RF on
By WZab - SP5DAA · #115955 ·
Re: Looking for the V2 Hardware Upgrade Info
Thanks David. Although this doesn't address the necessary upgrades to keep the IRFZ24Ns in place; it does help to convert a V2 to a V3. > > >
By JJ - W9JES · #115954 ·
Re: sBitx v3 stopped producing RF output after long FT8 operation #power #rf #sBITX_v3
Hello Evan, I have verified that bias circuitry works properly. I have even checked that the finals have full power suply voltage on their drains (13.3V) and that its DC value drops to ca 1V when I
By WZab - SP5DAA · #115953 ·
Re: uBITx v3 upgrade
Fred, There is a different answer for each individual.? Do you want to operate CW regularly?? Do you use headphones regularly?? ?Do you want to gain skills in hardware, software, or both?? These
By Evan Hand · #115952 ·