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Hi Brian, I have my U3S on a 10M beacon frequency. And I use the QRP-Labs PA kit. The shaping is accomplished on the PA kit assembly. So on your U3S if you don't use that particular PA you would not

Allison,? in order of importance to me is the following,? 1) drive level, those SBL 1 mixers want +7dBm? 2) frequency I'd like to try reaching 2 meters, 222Mhz would be nice. 432MHz would need

Hi Justin. One answer is to use a Modamp as a buffer? After all the BS170 can deliver 300mW or more and the typical SBL1 will need just 10mW....or perhaps 20 or 50mW if you select one of the hi drive

Thanks, I will.

I would check the LPF capacitors.

When I finished building the kit I had receiver problems, all traced to bad/cold solder joints. The transmitter appeared to be working fine, 5 watts out with 15 VDC supply. Then while further testing,

I built the kit a few weeks ago and want to use it with GW3UEP's 100W PA on 630m. The last post I can find relating to CW is #18874. Ken G4APB notes that TX CW works as long as SHAPING is set to 00.

Tim, Don't be silly... of course its macro hurts. Allison

Justin, I can see wanting or needing the bandwidth.? FYI the bs170 will not make it to 300mhz and even 6pf at 100mhz is getting to 200 ohms. If cross talk is the concern the easiest way is multiple

I have considered the single gate 74 series inverters, so far the fastest one I can find only goes to 100MHz. I'd like to support the entire range of the Si5351a. so as close to 300Mhz as can be would

On 14/09/2018 12:11 PM, ajparent1/KB1GMX wrote: [snip] > > It the BS170 has a input C of 60pf at*_3mhz_* that's about 800 ohms not > counting Miller feedback and at_*30mhz*_ your down to 85 ohms.

Hans, thank you very much for the explanation of CLK1 not enabled when receiver is muted.? This transceiver kit has certainly been an excellent learning experience! 73 John KF6QPC

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