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On Thu, Sep 13, 2018 at 07:11 PM, ajparent1/KB1GMX wrote: Cant say as the input capacitance of that type of mosfet is not that high. should be: Can't say as the input impedance for that type of mosfet

Cant say as the input capacitance of that type of mosfet is not that high. Keep in mind at DC its infinite.? At RF its current flowing into and out of (source and sink) the gate capacitor.? You want

Allison,? the end use is driving an SBL 1 mixer, the reason I ask about the input impedance is I want to minimize the loading on the Si5351a synth chip.? -Justin N2TOH

Like most fets both junction and mos the input impedance is far higher than? 50 ohms and also reactive. To get a fet to match to a DBM output requires a feedback circuit and often resistive

73 Alan G4ZFQ

They say bride comes before the fall.?I blew my AVR by failing to remove the link between the PA and +5V and applying 12V. Unfortunately the replacement got stuck in the Turkish mail system for ages

Hi, Hans? if I may ask what is the input impedance of the BS170 based amplifier? I'm interested in driving some Mini Circuits SBL 1 mixers and had hoped that the BS170 single device amps would fit

Hi John Apologies for jumping late into the discussion. During TX or receiver muting, only one of Clk1/0 is active, and the frequency is set to 27MHz. This is a nice trick which I developed that

Hello Chris and Alan, after hooking up my oscilloscope, I noticed both CLK0 and CLK1 are active.? The only? time CLK1 would be 0 is after placing the QCX in menu 9 Test Equipment | 9.2 RF Power and

Hello Alan, I think this is the info he needs from a quick search of my folder: "This has come around before, but here's a reminder. The part you want is the Si5351A-B. It comes in a 10-MSOP package.

John, Yes, but bad joints/bridges can show afterwards. Have you checked for grounding or with the scope yet? The one used is not pre-programmed, if you look back in the posts (search) the exact

Hello Alan, Thank you for your reply.? As mentioned previously, after building the QCX, the voltages of both clocks WERE the same and for some reason CLK1 is now 0v.? As for the SI5351A_MSOP, it is

John, A few faulty components have been reported but faulty new components are rare. More often faulty components are due to a constructor's mistake. Most faults found are due to bad solder joints or

Correction: That’s 100 mA and 225 mA (not mW). John AA7US

From an early thread.... Regarding the?clock and the checksum validation. I have not done a Clock firmware release since the checksum validation release on the U3S. Next clock firmware release, I

Andy, I finished building and testing my OCXO today... I started out trying a 15K resistor for R5 but found it limited the BS170 MOSFET's gate voltage too much. ?I could only get about 2.95 volts

After building the 20m QCX I checked voltages and at that time I was reading ~1.70 on both CLK0 & CLK1.? Last night, I was troubleshooting another problem and decided to re-check the voltages and

M0RON for the win! I tweaked my ref osc up by 1khz. Now the spotters I see have my freq spot on or w/in 100hz at numerous frequencies. Lacking anything better, I may be able to live with that. Thanks

Hi Ken, I checked Clock Kit page on web and there is no info about any improvement in C1.01a - only a compilation method change :-( (see screenshot) In FILE section here on groups.io there is only

Andy, I did say "I hope I got that right..." I did not:-) Maths was never my best subject. 73 Alan G4ZFQ