Topics

Fading during receive #ubitxv6


KB9WOO
 

I think I need to be educated a little, or maybe I need a better antenna or location (ok, I know both are true).  I am noticing that when tuning in a signal, it will be ok for a moment, then seems to fade away and I have to chase it to tune it back in.  Is that just SSB and/or weak signal, or could it be something with the radio?

I thought I may have buggered my frequency alignment a bit so I don't know if maybe I have multiple things going on.  I have been using an end fed no tune kit from QRPguys, but don't have much height.  Sometimes I can get WWV and sometimes not, so maybe I'm getting ahead of myself blaming the alignment.  I do not have an antenna tuner, either.  When I do get WWV, it is very weak.

As far as a better antenna, I'm leaning strongly towards a mag loop.  I think that could better suit my operating environment/conditions.

So, is this fading to be expected/normal with my less than optimal antenna height and location, or what do I need to learn?

Just looking for ideas, pointers, education, chitchat on these things.

Thanks all.

--
Mark, kb9woo
Milwaukee, WI uBITX v6


Robert D. Bowers
 

That is most likely propagation conditions, unless you mean the frequency is shifting ("drift") - which would be rather unlikely with the newer rigs.  It's not unusual at all to have signals fade in and out - especially when conditions are marginal.

As far as WWV... that too is very dependent on conditions.  We're just coming off of a sunspot minimum, and most of the time WWV reception here was marginal at best (depends a lot on the time of day as well).

Bob
N4FBZ

On 6/10/20 9:35 AM, KB9WOO wrote:
I think I need to be educated a little, or maybe I need a better antenna or location (ok, I know both are true).  I am noticing that when tuning in a signal, it will be ok for a moment, then seems to fade away and I have to chase it to tune it back in.  Is that just SSB and/or weak signal, or could it be something with the radio?

I thought I may have buggered my frequency alignment a bit so I don't know if maybe I have multiple things going on.  I have been using an end fed no tune kit from QRPguys, but don't have much height.  Sometimes I can get WWV and sometimes not, so maybe I'm getting ahead of myself blaming the alignment.  I do not have an antenna tuner, either.  When I do get WWV, it is very weak.

As far as a better antenna, I'm leaning strongly towards a mag loop.  I think that could better suit my operating environment/conditions.

So, is this fading to be expected/normal with my less than optimal antenna height and location, or what do I need to learn?

Just looking for ideas, pointers, education, chitchat on these things.

Thanks all.

--
Mark, kb9woo
Milwaukee, WI uBITX v6


KB9WOO
 

That makes sense and I'm glad I asked.  Thank you.

--
Mark, kb9woo
Milwaukee, WI uBITX v6


Jeff Debes
 

  Good luck , let us know how its working!



On Jun 10, 2020, at 4:17 PM, KB9WOO <kb9woo@...> wrote:

That makes sense and I'm glad I asked.  Thank you.

--
Mark, kb9woo
Milwaukee, WI uBITX v6

--
jeff.debes@...


ajparent1/kb1gmx <kb1gmx@...>
 

On Wed, Jun 10, 2020 at 06:35 AM, KB9WOO wrote:
As far as a better antenna, I'm leaning strongly towards a mag loop.  I think that could better suit my operating environment/conditions.
Compared the wire you are using its likely not going to be a better antenna,
expensive likely but not better.

Making an effort to get what you have higher up might help depending on how high it is
and what direction its oriented.
 
Likely you have more than one issue as well.  But from what you wrote its
hard to tell where to start. 

Allison
---------------------------------
No direct email, it goes to bit bucket due address harvesting in groups.IO


Dale Parfitt
 

Magnetic loops (or more correctly, Small Transmitting Loops) unless very carefully designed are an  inefficient antenna. This is not an issue for receiving HF, but is a poor choice for transmitting from  a low power rig. The more efficient the loop is, for a given diameter) the narrower is the bandwidth- this then requires constant retuning of the antenna as you QSY. Mounting the STL close to the ground (despite what you might read on the internet) then also introduces ground losses into an already inefficient antenna.

I would go with Allison’s and other’s recommendations to try to improve your current antenna. QSB (fading in signal strength) is  perfectly normal on signals propagated by the ionosphere.

Try different bands at different times of the day and have fun,

 

Dale W4OP

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of ajparent1/kb1gmx
Sent: Wednesday, June 10, 2020 5:46 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Fading during receive #ubitxv6

 

On Wed, Jun 10, 2020 at 06:35 AM, KB9WOO wrote:

As far as a better antenna, I'm leaning strongly towards a mag loop.  I think that could better suit my operating environment/conditions.

Compared the wire you are using its likely not going to be a better antenna,
expensive likely but not better.

Making an effort to get what you have higher up might help depending on how high it is
and what direction its oriented.
 
Likely you have more than one issue as well.  But from what you wrote its
hard to tell where to start. 

Allison


Bob Lunsford
 

Propagation has a bearing on WWV signals. This works with time of day and some other factors. Depends on where you are located relative to WWV's transmit locations (Colorado or Hawaii).

The antenna is also a huge factor on transmit and receive. A G5RV works for some on some frequencies but while I have a G5RV, I also have an endfed dipole with 53-ft radiating element, 16-ft counterpoise and 20-ft of coax feedline fed through a 1:1 balun to decouple the feedline so RF does not get into the shack. Also, the feedline MUST be below the counterpoise angled down at 45-deg from the 9:1 unun.

If you have another radio, check to see if the signal levels are better or pretty much parallel to what you get on the V6. This way, you can get an idea if the V6 is not processing the signal as it should and indicate some problem with the RF/IF stage/s.

Let us know or your further findings.

Bob — KK5R

On Wednesday, June 10, 2020, 9:53:03 AM EDT, KB9WOO <kb9woo@...> wrote:


I think I need to be educated a little, or maybe I need a better antenna or location (ok, I know both are true).  I am noticing that when tuning in a signal, it will be ok for a moment, then seems to fade away and I have to chase it to tune it back in.  Is that just SSB and/or weak signal, or could it be something with the radio?

I thought I may have buggered my frequency alignment a bit so I don't know if maybe I have multiple things going on.  I have been using an end fed no tune kit from QRPguys, but don't have much height.  Sometimes I can get WWV and sometimes not, so maybe I'm getting ahead of myself blaming the alignment.  I do not have an antenna tuner, either.  When I do get WWV, it is very weak.

As far as a better antenna, I'm leaning strongly towards a mag loop.  I think that could better suit my operating environment/conditions.

So, is this fading to be expected/normal with my less than optimal antenna height and location, or what do I need to learn?

Just looking for ideas, pointers, education, chitchat on these things.

Thanks all.

--
Mark, kb9woo
Milwaukee, WI uBITX v6


Evan Hand
 

One note when comparing the ubitx to another radio: the stock ubitx does not have AGC.  I would suggest turning off the AGC on the comparison radio to validate the "fading" is caused by propagation.

73
Evan
AC9TU 


Patrick Pugh Sawian
 

The upside of this is that it can be used as a guitar/synth effect, which is interesting. Am still tweaking with a MIDI controller to help me recall the effect via a USB switch run by a duino that will switch on the radio/mix  on a MIDI note.

73ees,
Pat
VU2OGA  


KB9WOO
 

Thanks everyone, I appreciate the feedback.  I don't have a radio to compare to, but it looks like it will be dry out today, so I'm hoping to setup and give it another go later on.

I will report back.

--
Mark, kb9woo
Milwaukee, WI uBITX v6


Curt
 

Mark

Good advise here already. Try different bands. If you can get the middle of that antenna up more than 20 feet you should he hearing something. EFHW antennas take some patience to tweak them for best match across the bands, but what you have may receive okay. BFO calibration is critical, find an AM signal and listen to both lsb and usb to see if they sound the same. Frequency calibration will not affect what you hear, only dial accuracy.

HF signals can fade a lot.

Curt wb8yyy


KB9WOO
 

It ended up raining last night and supposed to rain at some point today as well, so I never got a chance to get back out there.  Wont give up though!


--
Mark, kb9woo
Milwaukee, WI uBITX v6


KB9WOO
 

Got the end-fed a little higher yesterday in an inverted V and was receiving pretty good. Used headphones to hear the weaker signals so I think I'm in ok shape. However, I don't think there's any audio from my microphone. I did drill a bigger hole in it, but don't think that helped. I've read many posts here about the mics, so I'll have to decide which path I'm going down to get that part working.

Thanks again for the help. I appreciate you all.

--
Mark, kb9woo
Milwaukee, WI uBITX v6