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Re: Hellschreiber on U3S #u3s
You need to use the Slow Hell mode for grabber work. Use an Fsk bandwidth setting of about 4 or 5 Hz. If my memory serves me right and there have been no fundamental firmware changes, then the U3
By - Andy - · #26744 ·
Re: Solder temp for QCX Board
Thanks to all..... I'm using 350C and it seems to be be pretty similar to the 30 watt iron I had before. I appreciate all the input. 73, ?Robert KR4VT
By rtharp0001@... · #26743 ·
Hellschreiber on U3S #u3s
Is anyone successfully using Hellschreiber mode on U3S with firmware v3.12a? I just tried regular and DX Hellschreiber today for the first time and am getting a splattering mess about 20 Hz wide when
By AA7US · #26742 ·
Re: BS170 amp input impedance
Justin, For 2m you may find the phase noise fairly high.? Just listening to it bare with my?2M system suggests that. For 222 and higher its not what you want to use the harmonics sound bad! For 432
By ajparent1/kb1gmx · #26741 ·
Re: Ultimate3s v3.12a release and CW operation
Thanks Bill, I appreciate the clarification. Brian VE7JKZ
By Brian Summers · #26740 ·
Re: Ultimate3s v3.12a release and CW operation
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
By Bill Oelker · #26739 ·
Re: BS170 amp input impedance
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
By Justin Kelly · #26738 ·
Re: BS170 amp input impedance
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
By David Bowman <g0mrf@...> · #26737 ·
Re: My latest QCX 40 problem...
Thanks, I will.
By Jim - K9DD · #26736 ·
Re: My latest QCX 40 problem...
I would check the LPF capacitors.
By g4sra · #26735 ·
My latest QCX 40 problem...
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,
By Jim - K9DD · #26734 ·
Ultimate3s v3.12a release and CW operation
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.
By Brian Summers · #26733 ·
Re: BS170 amp input impedance
Tim, Don't be silly... of course its macro hurts. Allison
By ajparent1/kb1gmx · #26732 ·
Re: BS170 amp input impedance
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
By ajparent1/kb1gmx · #26731 ·
Re: BS170 amp input impedance
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
By Justin Kelly · #26730 ·
Re: BS170 amp input impedance
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.
By Tim <VK2XAX@...> · #26729 ·
Re: QCX - CLK0 & CLK1 Previous & Current Readings #qcx #clock
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
By j.capel@... · #26728 ·
Re: BS170 amp input impedance
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
By ajparent1/kb1gmx · #26727 ·
Re: BS170 amp input impedance
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
By ajparent1/kb1gmx · #26726 ·
Re: BS170 amp input impedance
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
By Justin Kelly · #26725 ·