Topband: Digital modes on TB and power required

[Jim Jim]

Guys,

First of all in many cases the reason we need really high power on any mode is because other hams on the band are using it and they cover us up... so it is mine is bigger than yours.  Now to be fair that is not always the case I know but it happens far too much.  Since we are in the years of the bottom of the solar cycle we actually may need more power.  Also you can not compare doing meteor scatter or EME work with HF work.  There you absolutely need power unless you have stacked 18 element beams or something.  But I have seen very very few instances when 50 watts wont get the job done EVEN on 160M.   and NO I don't run my RX with a wide open front end I have an IC 7300 and I trim my RX and TX filters to a reasonable width based on the mode I am running.  Common sense (and good engineering principals) teach you if you cut the RX bandwidth the signal goes up in strength. You have only to try that with CW to learn that.    and for those of you that don't understand the principal of RX front end overload try having a neighbor 4 miles away as the crow files who is trying to call the same DX you are wanting to work he can be half a kHz away and still give you problems even with a good RX. Now you guys with the really big antennas can mitigate some of this but us little pistols have only once choice ... wait until you neighbor is done.  And to be neighborly both my neighbor and I do just that.   Something to also consider when you run any digital mode even RTTY and you do it through a sound card you should not be drawing ANY.. not even a little ALC and if you do you not only will make it hard for others to copy you but you could easily cause all kinds of splatter on the band, you have only to listen to some to the signal on 40 and 20 meters to see this.

I am not saying any of this to flame or inflame anyone it is simply the way it is. High power is RARELY necessary on the lower bands.


Doubt me?  Set your transceiver up on WSPR and set it to 20w  and find out.  When TB was open I was heard all over the world with that power .. and yes even VK.  If all of this is not convincing then follow the FCC rules .. use only the power necessary to do that job


Oh by the way many of these digital modes are high duty cycle and could do damage to your transceiver. 


Jim



On the higher bands, low power generally gets the job done. But digital
folks on 160 need to rethink a few things. Ideally, we should ALL just bump
our output up to 100 watts. But that's just not gonna happen.  😊

I don't have the time right now to add more, but I hope this thread nets
some useful suggestions to minimize QRN in the 160m digital portion.

73, Mike
www.w0btu.com http://www.w0btu.com/