6M has been the magic band for many decades before me.? ;)
As a hard core VHF/UHF op I spend a lot of time on 6M.? How hard core?
My first three HB radios were for 6, they remain in service since.? 6M is
not high power, its good antennas, yagis and they are not hard to build.
The entry level is horizontal 3 elements on a 6ft boom and a few watts.

10M is a second favorite.? Its open more than closed.? The problem is everyone
is listening, no talking.? End of last cycle I got tired of hearing "10 is dead" so with a
tribander, end fed halfwave wire and qrp power [4W SSB] I worked 85 countries in
5 months.? There was TEP and Eskip enough that it included spots like MacMurdo
and the Falklands from W1 land.? Then a living got in the way... ;)

I hear its dead from many, they all answer the question, When did you call CQ there?",
they didn't.? ?If no one is talking someone has to make the first noise.? ? Generally true
most bands but generally 10 and 15 (and 17) will be daylite bands for a while and
occasional night skip.? Oh, and 6M is entering the E-skip season (least here in USA)
and EU too and that happens any time for a few minutes or hours.? The only way
to know is to be there.

Allison

Oh, and the pop eliminator looks like a 2n7000 board controlled by the T-R line. On a separate little board, much more simple than others I've seen. Five components total includes the mosfet. And a new test point TP1 ! And new jumpers where the little board connects. I haven't put the two 10X17 sheets side by side yet , and these still stand out.? A 1uf with a diode and resistor give the mute timing just enough time.?

On Thu, May 31, 2018 at 3:43 PM, Michael Shreeve <shreevester@...> wrote:

I believe Ashhar is using the RD15HV IN rV4 . he ha done major mods, A complete descrete direct coupled audio amplifier circuit, a pop eliminator, an AGC , Lots of stuff. He claimed it was a dollars worth of parts, but, the board is a massive change. The Finals section in the schematic is very confusing and looks like a direct coupled Mosfet circuit, but that's probably not the case. Hopefully he's reading this , I printed the schematic 10x17 today and the changes stood out like a "western sore thumb" . Very tempting to have a second board.?

On Thu, May 31, 2018 at 2:46 PM, Mike <msmith@...> wrote:

Thanks for the replies . . .?I figured they were meant to be options. May be better just to provide a text-box footnote in?schematic.

I've made dozens of FT8 contacts with a scratch built ubitx(V3) using the 510's, typically 10W PEP,? minimal heatsink, no fan, no?enclosure?. . . . the 510's?are actually quite rugged, stable, and predictable.

It's part of what makes it a fun build - they're cheap to replace when you drive them into oscillation and then *poof* !

--

Michael Shreeve N6GRG

--

Michael Shreeve N6GRG

I believe Ashhar is using the RD15HV IN rV4 . he ha done major mods, A complete descrete direct coupled audio amplifier circuit, a pop eliminator, an AGC , Lots of stuff. He claimed it was a dollars worth of parts, but, the board is a massive change. The Finals section in the schematic is very confusing and looks like a direct coupled Mosfet circuit, but that's probably not the case. Hopefully he's reading this , I printed the schematic 10x17 today and the changes stood out like a "western sore thumb" . Very tempting to have a second board.?

On Thu, May 31, 2018 at 2:46 PM, Mike <msmith@...> wrote:

Thanks for the replies . . .?I figured they were meant to be options. May be better just to provide a text-box footnote in?schematic.

I've made dozens of FT8 contacts with a scratch built ubitx(V3) using the 510's, typically 10W PEP,? minimal heatsink, no fan, no?enclosure?. . . . the 510's?are actually quite rugged, stable, and predictable.

It's part of what makes it a fun build - they're cheap to replace when you drive them into oscillation and then *poof* !

--

Michael Shreeve N6GRG

Thanks for the replies . . .?I figured they were meant to be options. May be better just to provide a text-box footnote in?schematic.

I've made dozens of FT8 contacts with a scratch built ubitx(V3) using the 510's, typically 10W PEP,? minimal heatsink, no fan, no?enclosure?. . . . the 510's?are actually quite rugged, stable, and predictable.

It's part of what makes it a fun build - they're cheap to replace when you drive them into oscillation and then *poof* !

More from the thinkery, Mike:

TP20 should give a good meter point. There's a 0.1uF to earth there, but at low freq and Z its Z won't affect much.
..and theoretical, 'cos I don't actually have one: stalled with bitx-40 and horrific QRM at the QTH :( .

73
Dex, ZL2DEX

On 5/31/2018 4:53 PM, Richard Spohn wrote:

It's all due to marketing!  10 meters is called the "Magic Band".  And
everybody loves magic. - Rich WB2GXM

On 5/30/18, Bo Barry <bobarr@...> wrote:

I'm constantly surprised at the interest in 10 meters. I always check 15. If
its dead I go to 20. If it has anything on it I check 10 and hear nothing
here in NC with a simple EFHW..

But 10 was a blast back in 1954!!? ?:)

73, Bo W4GHV since '54

OK, I thought about this can of worms I opened on the ride home. Given the stores are 60 miles from the mountain top home I am staying at this summer I had roughly 45 minutes to sort through the various responses.

First, we should agree that the metric that establishes the accuracy one is aiming for is wave? lenght. Wave length of course is the distance propagated in one complete cycle. So Jerry is correct in that if your aim is to set an oscillator at a set frequency then being off by as much as 300 hz when using? a 30 MHz signal as a reference is equivalent to being off by 10 hz when using a 1 Mhz signal as a? reference. This is due to 10 cycles at 1Mhz and 300 cycles at 30 Mhz, when viewed as occupying distance, are equal in lenght.

If I have bad hearing it is normally at the low or high end of the spectrum and what Jerry pointed out shows that I can still obtain the accuracy of someone with better hearing by using a higher frequency for a reference signal and if our hearing is equivalent then I simply obtain higher accuracy by using the higher frequency reference signal.

As the other gentleman pointed out being able to have accuracy that resolves to perfection is most likely not even possible because of capacitor issues that end up blocking or at least attenuating the lowest of the lows in terms of audio signals.

However, I do disagree with defining theoretical so as to indicate other than actual conditions for while the theoretical and actual may not coincide there are times that they do.

Thank you all for chipping in to this discussion brought on by my thinking out loud. Its been interesting.

_._,_._,_