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Re: question for psk users

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Tony

Re: [Elecraft email list

Hi is the email list down?
Tony

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Joe Subich, W4TV-4

Re: question for psk users

In reply to this post by ve3dvy

On 5/2/2012 1:07 PM, David Moes wrote:
> You are assuming that everyone has the luxury of narrow roofing
> filters and can filter out the week and reject unwanted strong
> signals. most PSK stations are not blessed with a K3 and are not able
> to suppress strong signals. before I had a K3 2.4 was the narrowes I
> could do. most afordable rigs today still stop at 3khz (FT950) and
> some even wider.

That's not true. Every rig manufactured today provides a CW filter
option that works very well for reducing/controlling the AGC blocking
issue. The FT-950 provides selectivity down to 500 Hz in its "PKT"
modes as do many other "affordable" rigs.

73,

... Joe, W4TV

On 5/2/2012 1:07 PM, David Moes wrote:

> You are assuming that everyone has the luxury of narrow roofing
> filters and can filter out the week and reject unwanted strong
> signals. most PSK stations are not blessed with a K3 and are not able
> to suppress strong signals. before I had a K3 2.4 was the narrowes I
> could do. most afordable rigs today still stop at 3khz (FT950) and
> some even wider. You should use as little power as possible to
> conduct your QSO. where I come from that is the law. using high
> power to conduct a PSK31 qso is rarely necessary. most other PSK
> users are running less than 30 W and if you can hear them you probably
> don't need 100+ watts to talk back. I agree that it is needed in
> some cases but one should only shout when you need to and talk normal
> or even whisper if you can.
>
>
>
> David Moes
> VE3DVY
>
>>
>> The reason why a strong signal will "annihilate all the other PSK
>> signals" is that most users are trying to receive an entire 2.5kHz
>> bandwidth in one gulp. This means that even one strong signal within
>> that bandwidth will activate the AGC and drive all the other signals
>> down.
>>
>> Regrettably most PSK users don't understand what is happening, so they
>> have to rationalize it into simpler terms like "It's a crime to be
>> loud."
>
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Jim Brown-10

Re: question for psk users

On 5/3/2012 5:51 AM, Joe Subich, W4TV wrote:
> That's not true. Every rig manufactured today provides a CW filter
> option that works very well for reducing/controlling the AGC blocking
> issue. The FT-950 provides selectivity down to 500 Hz in its "PKT"
> modes as do many other "affordable" rigs.

Yes, but some rigs are more versatile than others, and some operators
don't bother to learn enough about their radios to use the options that
they provide. Some rigs may not allow digital transmission at the
frequency where that filter is centered, or may not allow it to be
switched in for SSB modes. In other cases, the architecture of the rig
may require that a different input of the radio be used for the digital
modulation. For example, I think I remember correctly that I had to
feed the Patch input of my FT1000MP for AFSK to center it in my RX
filters and for VOX to work. Or maybe it was the Packet input as you
noted for the FT-950. There's also the matter of learning to use all
the controls on the radio to best advantage, including, as others have
suggested, the RF gain control. Back in the old days, AGC was rarely
used on CW, we set AF gain to a suitable level and rode the RF gain
control as needed, and switched in a crystal filter to bring out the
signal we were interested in.

One of the things about becoming a better operator is taking the time to
learn these things. Those who choose not to do so will continue to be
limited by their ignorance.

73, Jim K9YC
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ve3dvy

Re: question for psk users

In reply to this post by Joe Subich, W4TV-4

Its true that most modern rigs have narrow filters for CW etc but most
rigs use DSP in the final IF stage to do this. This narrow passband is
not protected with narrow roofing filters. look at the FT950, AGC
comes after the roofing filter and before the second and third IF. the
narrowest option for the roofing filter is 3Khz and 20khz for the
FT450 A strong signal outside the dsp passband but still within the
passband of the roofing filter will still knock out the week signals no
matter how hard you try. This holds true for many of the the rigs in
the big three linup excluding some of the high end ones that most of us
cant afford. one of the advantages of the K3 is its ability to use
any roofing filter in any mode. making it awsome for digital. most of
the other in its price range don't have this ability or even offer
narrow roofing filters.

Not everyone can afford a K3 or FT5000mp I consider myself lucky to
have a K3. before I had it I often just shut down as my older rig
could not filter out that guy 400hz down bragging that he was running
200W psk to the guy that just gave him a 599 ++ report. yea it was 20
years old and wouldnt let me use the CW filter in ssb. It all boils
down to the same thing. operate with consideration don't shout when
you don't need to. you should operate the minimum power that is
needed to maintain communications.

> On 5/2/2012 1:07 PM, David Moes wrote:
> > You are assuming that everyone has the luxury of narrow roofing
> > filters and can filter out the week and reject unwanted strong
> > signals. most PSK stations are not blessed with a K3 and are not able
> > to suppress strong signals. before I had a K3 2.4 was the narrowes I
> > could do. most afordable rigs today still stop at 3khz (FT950) and
> > some even wider.
>
> That's not true. Every rig manufactured today provides a CW filter
> option that works very well for reducing/controlling the AGC blocking
> issue. The FT-950 provides selectivity down to 500 Hz in its "PKT"
> modes as do many other "affordable" rigs.
>
>

KD8NNU

Re: question for psk users

In reply to this post by Glen, W6GJB

HI Roland,

When I spend some radio time this weekend I send them to you.

There are two sets of macros. One for HRD for the radio commands, then
a set in DM780 to use them.

They are not perfect macros, but they work for me. I was just happy
that I figured them out, I kinda programmed them with the hunt and peck
method.

If anyone else on the list wants a copy send me a note and I will send
them to you also. I would like to be able to give a little back to this
list as I get way more from all you gents.

Cheers
Don

~73
Don
KD8NNU

On Thu, May 3, 2012 at 10:24 AM, Rowland R Johnson wrote:

> Don,
>
> Any chance of getting a copy of the macros you developed for HRD?
>
> I was getting ready to do something similar. I have the K3, HRD,
> DM780, and a SignalLink USB. I ordered the 200 Hz roofing filter
> yesterday. The plan was to use the DM780 waterfall to locate a signal
> then use the Lo and Hi cut on the K3 to narrow the band to < 200 Hz
> around the station. I'd be counting on the K3 switching to the 200 Hz
> filter when the band got narrow enough. I was concerned that when the
> K3 switches to the 200 Hz filter that frequency would change resulting
> in the target signal moving out of the narrow band. I talked to
> Elecraft, but I'm not sure that I got my question across; so I'm still
> not sure it'll work like I want it to. Your solution doesn't depend on
> the frequency not changing.
>
> Using both a waterfall at 3 kHz and then a 200 Hz filter really is the
> best solution.
>
> Thanks,
>
> Rowland,
> AG6KN
> [hidden email]
>
> On 5/2/2012 4:16 PM, [hidden email] wrote:
>> I have macros built in HRD that allows me to quickly center a PSK RX
>> and
>> then I pop to mhy 200 hz filter to work them when every the adjacent
>> signals are messing with my decode. I constantly change between many
>> filter choices as necessary via macros in the software.
>>
>> I bought the 200 hz filter last year at Dayton after Wayne spent a
>> few
>> minutes of time with me explaining how to use the filters better to
>> my
>> advangate.
>>
>> Now I don't care what the other guys do because the K3 just does what
>> it
>> does best.
>>
>> ~73
>> Don
>> KD8NNU
>>
>>
>> On Wed, May 2, 2012 at 7:45 AM, briana wrote:
>>
>>> Guys,
>>>
>>> This rational is bogus. The PSK users have to get used to decoding
>>> one signal at a time with narrow filters if that's what is
>>> necessary.
>>> To expect to have 2 or 3 KHz free of strong signals is crazy.
>>>
>>> Dealing with this reality puts the burden on the receiving end. No
>>> way can you control what the rest of the wold does. This isn't the
>>> Magic Kingdom.
>>>
>>> Given that PSK is a narrow bandwidth mode, why not use that to your
>>> advantage?
>>>
>>> Other modes deal with strong adjacent signals, why not PSK?
>>>
>>> You bought a K3 for its high dynamic range and high adjacent signal
>>> handling capability. Why not use it for this purpose?
>>>
>>> Of course the argument ignores all the laws of physics and
>>> propagation. I suggest you run some VOACAP prediction
>>> calculations
>>> with 25 watts and look at what you can't work with 25-75 watts.
>>> You
>>> may not be interested in working the other side of the world, but
>>> others are.
>>>
>>> PSK isn't magic.
>>>
>>> 73 de Brian/K3KO
>>>
>>>
>>>
>>>
>>>
>>> On 5/1/2012 11:46 PM, Jon Perelstein wrote:
>>>> Eric KG6MZS asked why wouldn't you run more than 70w on PSK
>>>>
>>>> Because with the close spacing of signals in the various PSK
>>>> sub-bands, a
>>>> signal of more than about 50watts will completely annihilate all
>>>> the
>>>> other
>>>> PSK signals and make that sub-band unusable for everyone else. The
>>>> rule of
>>>> thumb for being polite on PSK is to operate 25-30w max. I won't
>>>> claim that
>>>> there aren't some who are operating more (you Cuban stations know
>>>> who
>>>> you
>>>> are), but many/most of us will avoid QSOs with people who are
>>>> obviously
>>>> running 50w+
>>>>
>>>> 73s
>>>> Jon, WB2RYV
>>>> ______________________________________________________________
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>>>>
>>>>
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>>>>
>>> ______________________________________________________________
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>> ______________________________________________________________
>> Elecraft mailing list
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>>
>>
>
> --
> Rowland R Johnson
> [hidden email]
>
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