N connectors by Huber&Suhner for example are rated 5.2KW@20MHz, 3.5KW@30MHz, 800W@1GHz etc. Amphenol specifies a peak power of 10KW no frequency given, so certainly low frequency only. 73 Peter Notic
My 2m equipment runs 2.5KW out via N connectors since 1988. Of course all my connectors and relays are made in Germany by Spinner or RFS and no Chinese or US crap. 73 Peter My 2M amp runs a solid 150
The brown insulated Amphenol PL259/SO239 have the worse smell when burned out... 73 Peter If a connector has Amphenol on it, can I assume it is a good one? I see several Amphenol connectors on eBay f
Q must be high if output impedance of the tube is high 73 Peter Bottom line is..there is no reason to run a sky high loaded Q on the upper bands..... including 6M. ___________________________________
Spark gaps are much cheaper. And nobody uses load variables made for 5 or 6 KV with a simple Pi net. 73 Peter Capacitors don't arc at the RMS voltage. They arc at the peak of the RF cycle. For 1500 w
I also use vacuum variables as load capacitors in high power amplifiers but for good reason, not for not existent high voltages. Loading capacitors in simple Pi circuits are stressed by current, not
It´s quite simple without measurements. Lets assume the amp is tuned for full legal output into a low SWR on 80m which needed 1000pf of load capacitance. Then suddenly the SWR goes sky high because t
No one building a 15KW amp will be that stupid to use 10-12 ga wire to connect the pi to the antenna. And that wire must be very long that you can measure a Z of 250-500 ohm. On the amps by Telefunke
Here in Germany 7/16 plugs for 1/2" Cellflex by RFS are 6,91 Euro, those for the more fexible SCF type are 7,19 Euro. In Germany we also use a similar but smaller DIN connector which is type 4.1-9.5
The negative screen current is caused by back bombardment of electrons from the anode to the screen grid 73 Peter I too have a problem with this explanation. Electrons gathered by the screen are 'pos
The use of not bypassed cathode resistors in the cathode lead of tetrodes sometimes is done on purpose to improve IMD by negative feedback, but those resistors are not large, around 10-15 ohms. 73 Pe
Extracted from http://en.wikipedia.org/wiki/Tetrode "As the screen grid is positively charged, it collects electrons, which causes current to flow in the screen grid circuit. This uses power and heat
I mount my tetrodes up side down Yes, and the electrons, frightened and confused, and not knowing which way is up, run in the opposite direction to the power supply or in the general direction of a l
Sure, always! At least in thinking... Hny Peter Are you positive? Alek. VK6APK On 31/12/2013 8:56 AM, Peter Voelpel wrote: -- From sunny Binningup, Western Australia. Family Businesses: Petkovic Air&
True, the total number of electrons increase, but their charges are opposite polarity. Secondary emission in a tetrode can occur when the anode voltages drops below screen voltage. In that case the e
Yes Jim, You are totally right, of course the electrons are always negative, if not there would be no flow from anode to screen or either. Its already a bit late ;-)) It is only the direction of elec
I can recommend Dominiques pages: http://f1frv.free.fr/main3h_SWR_Bridges.html 73 Peter I too would be very interested in any designs and / or practical implementations that anyone can recommend. I w
Don´t you think it depends on anode voltage and output impedance of the Tube(s)used? The switch is adequate when used in a 1500W amp on low to medium anode voltage. It will certainly arc if you use a
I guess with transformers the relay should switch in on the peak voltage. As current peaks 90 degree behind that should be the best moment with least surge current. 73 Peter But, unlike a mechanical
That 2m amplifier is not run zero bias but with normal screen and grid voltages for AB1. Power gain is about 13db. I know the builder quit well. You see more photos on his web site: http://www.dj5dm.