¿ªÔÆÌåÓý

ctrl + shift + ? for shortcuts
© 2025 Groups.io
Date
Re: Tuned input
Peter. This is NOT a band pass filter?? I am confused here.? I expected each band slot to have a band pass for that band and a cut off above and below. What I see is that I can adjust the match to
By W7WRX · #40015 ·
Re: Tuned input
Yes, a real easy way to tell is to look at the transfer function with omega equal 0. A non mathematical way is simply, if you put DC in will you get DC out? 73 ¨C Mike Mike B. Feher, N4FS 89 Arnold
By Mike Feher · #40014 ·
Re: Tuned input
Yes,those are 5 turns. A pi-filter with capacitors as shunt elements is a low pass filter, not a band pass filter. Differences from the instructions to the real world might be caused by stray and
By Peter Voelpel · #40013 ·
Re: Tuned input
So this would be 5? I have tried 7, 6 and 5 turns. NO band pass. Only a cut off past 40mhz. As I remove turns I require less and less cap on each side. With this winding it's 0pf on each side. If I
By W7WRX · #40012 ·
Re: Tuned input
If a wire goes through the center of a toroid, it counts and acts as a turn. It does not need to be looped around. 73 - Mike Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 Sent:
By Mike Feher · #40011 ·
Re: Tuned input
I removed 2 turns and still do not see band pass. What I see is a high pass at 40mhz. Below that it's pretty flat down the bands. It's supposed to be 7 turns of 20awg. Do the wire ends as they loop
By W7WRX · #40010 ·
Re: Tuned input
## I design and run the PI tuned inputs through software every other week...then verify on the
By Jim VE7RF · #40009 ·
Re: Tuned input
I got all the parts in and am building the board. I installed all the relays, the 10 meter A and B trimmers and the wound a toroid. 7 turns of 20 AWG With a dummy load on output of 50 ohms and the
By W7WRX · #40008 ·
Re: Anode Voltage Sag Issue
The resonating oil cap value is easily measured with any digital lcr meter. The real problem is measuring the choke.? I went through this with dahl / hammond a couple of years ago. A standard digital
By Jim VE7RF · #40007 ·
12 KW CCS ON 160-15M...USING THE 3CX-6000A7... PART 11
160 Meter Coil Installation, Paralleled Band Switch Contacts etc. Here the? 10 uh,? 160m coil is finally installed.....made from 1/4" tubing. Bandswitch contacts have been paralleled.? Taps to
By Jim VE7RF · #40006 ·
Re: Building my first amplifier. Where to start?
I have found at least 1/2 oz specs for RG-393..... and they are all over the map.? ?393 only has a? small 12 ga center conductor.....(.0808").? The issue is....whatever the puny center conductor
By Jim VE7RF · #40005 ·
Re: Building my first amplifier. Where to start?
Which of the 7 versions of the 8K ultra are we talking abt ?? ?The 8k manual I have sez...." 5400 dc no load.? Sags to 4800 vdc with a 1.25 amp CCS? cxr".? On the manual I have, they u
By Jim VE7RF · #40004 ·
Re: Building my first amplifier. Where to start?
Jim, Thanks for the explanation.? I understand the principle of what you are describing, eg the energy in the tank circuit causes the voltage to rise on the anode on the positive cycle, before
By desmond auld GI0UTE · #40003 ·
Re: Building my first amplifier. Where to start?
Alex, Thank you. That makes sense.? His ratings seem way to high to me.? Thanks for the confirmation.
By desmond auld GI0UTE · #40002 ·
Re: Anode Voltage Sag Issue
I don't have one of these but are there different primary taps that would alter the secondary voltage?
By mike repinski · #40001 ·
Anode Voltage Sag Issue
A fairly common occurrence is when the capacitor shunting the high voltage choke in the Henry swinging choke design changes value and does not resonate at the 120 hertz intended frequency. I challenge
By HaL Mandel · #40000 ·
Re: Building my first amplifier. Where to start?
If your 8k Ultra sags down to 4800 volts you have something wrong. Possible weak AC line, or failed Oil caps. I used a Fluke HV probe and mine sits at 5900 volts. panel meter shows 6000. At rated 5kw
By W7WRX · #39999 ·
Re: Building my first amplifier. Where to start?
RG393 will do it easily, it is specified 25kW at 10MHz, 9.5kW at 50MHz. 73 Peter, DJ7WW -----Original-Nachricht----- Betreff: Re: [ham-amplifiers] Building my first amplifier. Where to start? Look at
By Peter Voelpel · #39998 ·
Re: Building my first amplifier. Where to start?
On Tue, Jan 9, 2024 at 11:15 PM, W7WRX wrote: > > Its not hurting the tube.? You need to remember that this is Single side > band with a duty cycle of 15 to 20 percent.? Even with heavy processor is
By Jim VE7RF · #39997 ·
Re: Building my first amplifier. Where to start?
That fellow is well know for his total bs ratings. On that GU43B amp, he uses a pulsed 1.5 khz tone fed into the mic jack, with xcvr on SSB mode.? ?1 on, 4 off, pulsed at 30hz.? ( 20% duty cycle)?
By Jim VE7RF · #39996 ·