Hi Uwe, congrats to successfully debugging. Now it's time to try again today. :-) Is the antenna properly matched to 50 Ohm? If so you shold get some spots this evening, even with only with 1.3watts.
Hi Stefan, A general design rule for cascaded amplification stages is that the noise figure of the first stage is the most crucial one for the overal noise figure. So I would leave the gain before th
Hi Luis, That's certainly not the case for current Icom transceiver models. I wonder to which Icom gear you are referring to. Let's take a not so pricy Icom,the IC-7100. Its MDS in 500Hz BW was measu
Hi Luis, Yes,that's what I meant to say: It's all about local noise and/or antenna not about (Icom) rig sensitivty. I just wanted to back up my assertion by solid numbers and I'm no Icom dealer anywa
Hi Paul, http://abelian.org seems being not accessible the last few days including today, at least for me. Tried two different browsers to no avail. 73 Clemens DL4RAJ
The lower frequency limit of the through line elements is 450kHz. Therefore you won't get any sensible readings at 136kHz. Besides that SWR calculations from the forward and reverse power readings g
Indeed there is one element from 0.2-0.535 MHz (power range from 10W to 10kW full scale) but only for the 4410 Model.One element covers 7 power ranges. The elements fo the Bird 4410 Model are not co
Hello Andy, I seem to remember that NEC modelling done by a real expert in this area, W4RNL (sk), years ago revealed that a 'linear' (ungrounded) monopole of the same height as a folded monopole has
Hi Andy, I believe it's neither 3dB nor 6dB increase for ERP. What is squared by doubling the effective height is is Rrad. The increase in ERP is by far not so high and depends much on Rloss (ground
You can retrofit those ports by a PCI or PCIe card for little money. I am using one from Delock for connecting an old parallel port printer and a serial port card reader. It works flawlessly. 73 Cle
Hi Ken, I believe two of your component values are off. I calculate 201µH for the L next to the tubes,625pF for the shunt C and 1.1mH for the second L . For the 201µH L I would use iron powder (Amido
Addendum: Assuming an unloaded Q of 200 for the inductors and a Q of 1000 for the capacitor there are at the 300W level around: 2083V peak across the first L at 2.4A and 18W power dissipation 2090V p
Hi Ken, For the transformation by the T-pad I've used the well proven TLW3B by Dean Straw (it was / is(?) included with the ARRL Antenna Handbook). You can define unloaded Q for inductors and capacit
Here's a screenshot of the smith chart plot. The values differ slightly from the values calculated by TLW3B because the smith chart program uses lossless components whereas TLW3B uses lossy component
Hello Ken, I have mixed up input and output. So the correct values are 1.1mH **next to the tubes** and 201µH **next to the 50 Ohm load**. C stays the same. See RFsim screenshots. Sorry for the inconv
The schematic screenshot was empty,so here once more. P.S.The values in the smith chart plot from yesterday were correct anyway. 73 Clemens DL4RAJ Attachment: T-LowPass_475k_schematic.gif Description
Hello Ken, the L and C values *calculated by you* are about correct but_only_if_you_assume_lossless_components. The point however is that by choosing 1.1mH at the 50 Ohm side you set a very high load
Not ready for txing at present. Conditions seem to be good,I can hear even the second harmonic of the 1kHz modulation tone of BIA (474kHz) on 472kHz. I'm watching if I can hear a CQ call from you. 73
