Date   

Re: Spurs/Harmonics fixes for v4 based on v5 board design?

Dave Space
 

That's a neat trick too thanks.  I guess that could be way cheaper than desoldering braid.  I only recently learned that flux is on soldering braid as part of what makes that work.
(I had done a lot of soldering as a kid in high school doing electronic projects way too many years ago now, thought I knew something about soldering/desoldering - even put together heathkit computers way back then but as often happens you don't realize how much you don't know :) )



On Fri, Jan 25, 2019 at 04:39 AM, Raj vu2zap wrote:
Dave,

Use a wick. I normally strip some audio shielded wire or very thin coax like rg174 and dip it in some flux and sponge off the solder.
Then clean off the flux.

Raj

At 25-01-19, you wrote:
Ah Thanks. Ok I guess I still have a lot to learn about desoldering :) The needle is an interesting idea. If I was going to do a lot of through hole desoldering I would probably try that hakko vacuum tool - kind of expensive though if you don't do it that often looked like it did a nice job though from the video's I saw.

Luckily I was using a really small bit that didn't take the full hole size so hopefully didn't do any major damage.


Re: ubitx v4 spurs fix confusion #ubitx-help #ubitx

 

Thanks Gary,

Actually the component is covering the area!

I have some ceramic tipped screwdrivers for ferrite slug adjust. They are sharp and I used one to gently scrape away
the resist coating.

Raj

At 24-01-19, you wrote:
Yes, for this modification: remove the solder mask on the traces you have highlighted with the red circles.
Comment: the workmanship on solder mask removal was done so well on this example that there is no visible collateral damage.

Rgds,
Gary


Re: ubitx v4 spurs fix confusion #ubitx-help #ubitx

 

They are from a sample book. Marking is S+M which I understand is TDK.
They are shielded and have a DC resistance of less than 2 Ohms. 1210 size if I remember right.

Raj

At 25-01-19, you wrote:
Excellent picture - can you state the part number and mfr of the SMD inductors you are using?

Thanks,

73

Paul


Re: ubitx v4 spurs fix confusion #ubitx-help #ubitx

Paul Galburt - K2AYZ
 

Excellent picture - can you state the part number and mfr of the SMD inductors you are using?

Thanks,

73

Paul


Re: Spurs/Harmonics fixes for v4 based on v5 board design?

 

Dave,

Use a wick. I normally strip some audio shielded wire or very thin coax like rg174 and dip it in some flux and sponge off the solder.
Then clean off the flux.

Raj

At 25-01-19, you wrote:
Ah Thanks. Ok I guess I still have a lot to learn about desoldering :) The needle is an interesting idea. If I was going to do a lot of through hole desoldering I would probably try that hakko vacuum tool - kind of expensive though if you don't do it that often looked like it did a nice job though from the video's I saw.

Luckily I was using a really small bit that didn't take the full hole size so hopefully didn't do any major damage.


Re: Websdr

Jay - WS4JM
 

Another cool thing is you can record yourself for playback, an easier comparison than trying to listen to yourself after a short delay. I know when I try to listen myself directly I get confused.

Bill has a good point about lobes, you can check your performance at multiple sites to get a better idea of where each antenna works best.

73
Whiskey Sours 4 Jumping Monkeys
Jay


Re: Spurs/Harmonics fixes for v4 based on v5 board design?

Dave Space
 

Ah Thanks.  Ok I guess I still have a lot to learn about desoldering :) The needle is an interesting idea.  If I was going to do a lot of through hole desoldering I would probably try that hakko vacuum tool - kind of expensive though if you don't do it that often looked like it did a nice job though from the video's I saw.

Luckily I was using a really small bit that didn't take the full hole size so hopefully didn't do any major damage. 


Re: Comprison

iz oos
 

Exactly it is sensitive enough as tabletops or portables (degen 1103, Sangean 909 etc). The difference may be in other characteristics, like blocking, the presence of BPF, signal handling, but as for sensitivity it is very hard to find a real deaf one if everything is functioning well.


Il 25/gen/2019 09:12, "Lawrence Galea" <9h1avlaw@...> ha scritto:
Agree.
That's why I set the R8 without a preamp like the μbitx.
Re more audio on the R8 it was to explain on the different audio levels between the two receivers and a hint for those who would like more audio but with headphones should be ok on marginal signals.
As you said noise is the limiting factor on the lower frequencies and adding an amplifier will not only boost the signal but also the background noise.
However, it may, in relatively quiet locations, give a better copy as it may override the receiver internally generated noise and other losses within the receiver.
it would be interesting if someone who may have changed the receiver first 45 MHz IF section with hotter / lower noise transistors to report on the result.
Regards
Lawrence

On Fri, Jan 25, 2019 at 12:24 AM Curt via Groups.Io <wb8yyy=yahoo.com@groups.io> wrote:
Lawrence

Good data!  Please notice that sensitivity relates to our ability to copy a signal in the background (and rig supplied) noise -- not how much audio the receiver can pump into the air.  yes I perceive you already agree. 

how a receiver changes with preamp on and off does vary with how gain is built into the receiver.  a receiver can be 'gain limited' - meaning more gain would improve sensitivity or 'noise limited' - which you can guess means more gain does not improve sensitivity. 

depending upon our latitude, season etc. the background noise does vary.  at lower HF there is more noise in the atmosphere than our receivers can make, this only changes at the upper part of the spectrum.  in a quiet area with little man-made noise it will be interesting to compare the uBITX to receivers having a preamp on 28 MHz.  I am expecting only a small difference, less than one S-unit maybe.

likely many already know this, but QRN is propagated via the ionosphere - often from tropical regions.  cool stuff!

73 Curt


Re: mike

Lawrence Galea
 

Hi
get a long bolt, use a nut washer and spring washer to fix it to the case, then use another nut etc adjusted to the level of the other standoffs and use another nut etc to lock the pcb.
Regards

On Fri, Jan 25, 2019 at 12:17 AM Martin KM6TCD <peaceofandalus@...> wrote:
I've been admiring my bitx40 for a while, nice looking board.
Finally, I knuckled under to build it and found a couble of problems.
 
1. no mike.
 
2. One standoff has no threads - it happens.
    Furthermore, it could use about 2x as many standoffs. (The Radino should not be connected solely with ribon cable.)
 
What do I need to do?
 
m
78
 
 


Re: Comprison

Lawrence Galea
 

Agree.
That's why I set the R8 without a preamp like the μbitx.
Re more audio on the R8 it was to explain on the different audio levels between the two receivers and a hint for those who would like more audio but with headphones should be ok on marginal signals.
As you said noise is the limiting factor on the lower frequencies and adding an amplifier will not only boost the signal but also the background noise.
However, it may, in relatively quiet locations, give a better copy as it may override the receiver internally generated noise and other losses within the receiver.
it would be interesting if someone who may have changed the receiver first 45 MHz IF section with hotter / lower noise transistors to report on the result.
Regards
Lawrence

On Fri, Jan 25, 2019 at 12:24 AM Curt via Groups.Io <wb8yyy=yahoo.com@groups.io> wrote:
Lawrence

Good data!  Please notice that sensitivity relates to our ability to copy a signal in the background (and rig supplied) noise -- not how much audio the receiver can pump into the air.  yes I perceive you already agree. 

how a receiver changes with preamp on and off does vary with how gain is built into the receiver.  a receiver can be 'gain limited' - meaning more gain would improve sensitivity or 'noise limited' - which you can guess means more gain does not improve sensitivity. 

depending upon our latitude, season etc. the background noise does vary.  at lower HF there is more noise in the atmosphere than our receivers can make, this only changes at the upper part of the spectrum.  in a quiet area with little man-made noise it will be interesting to compare the uBITX to receivers having a preamp on 28 MHz.  I am expecting only a small difference, less than one S-unit maybe.

likely many already know this, but QRN is propagated via the ionosphere - often from tropical regions.  cool stuff!

73 Curt


Re: Spurs/Harmonics fixes for v4 based on v5 board design?

Bob Lunsford
 

I agree that the drill is a bad idea because it might drill
out the plated-through hole. I have an old ice pick that
serves me as would a darning needle. It's iron and the
solder does not stick to it.

Bob — KK5R


On Thursday, January 24, 2019, 11:14:34 PM EST, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:


Bad idea to drill out the solder in those holes.
Tim's darning needle is a much better idea.

Those holes are plated through, a vertical cylinder of metal plating added to the hole during board fabrication
that connects traces on the top to traces on the bottom.  If the drill is too big, you will cut that connection. 
  
Jerry


On Thu, Jan 24, 2019 at 07:01 PM, Timothy Fidler wrote:
If you heat up the covered copper land and thrust in a darning needle , say 1.5mm diameter,  you can forget  the jeweller's drill.  Solder will not stick to chrome plate.
 


Re: Spurs/Harmonics fixes for v4 based on v5 board design?

Jerry Gaffke
 

Bad idea to drill out the solder in those holes.
Tim's darning needle is a much better idea.

Those holes are plated through, a vertical cylinder of metal plating added to the hole during board fabrication
that connects traces on the top to traces on the bottom.  If the drill is too big, you will cut that connection. 
  
Jerry


On Thu, Jan 24, 2019 at 07:01 PM, Timothy Fidler wrote:
If you heat up the covered copper land and thrust in a darning needle , say 1.5mm diameter,  you can forget  the jeweller's drill.  Solder will not stick to chrome plate.
 


Re: mike

David Nelson
 

I took the electret unit that came with the bitx 40 kit and the push button
and mounted them in a piece of 3/4 pvc pipe and it works very good. 
Mine also had a standoff with no threads. The bitx 40 works extreamly well.
Good luck.  Dave  kc2ipx

On Thu, Jan 24, 2019 at 6:52 PM Doug W <dougwilner@...> wrote:
Martin,
Just to double check, the mic is just an electret mic like the picture below.  I don't have one in front of me to measure but it is approximately 10mm in diameter.




--
www.bitxmap.com


Re: Spurs/Harmonics fixes for v4 based on v5 board design?

Timothy Fidler
 

If you heat up the covered copper land and thrust in a darning needle , say 1.5mm diameter,  you can forget  the jeweller's drill.  Solder will not stick to chrome plate.

 

Timothy E. Fidler : Engineer BE Mech(1) Auckland , NDT specialist AINDT UT /RT3 , MT2 CB #2885, 
Telephone Whangarei   022  691 8405
e: Engstr@...



----- Original Message -----
From:
BITX20@groups.io

To:
<BITX20@groups.io>
Cc:

Sent:
Thu, 24 Jan 2019 16:33:43 -0800
Subject:
Re: [BITX20] Spurs/Harmonics fixes for v4 based on v5 board design?


Yep I just figured I would do the rest for good measure... though didn't realize how bad I was at desoldering.

To amend my previous statement it took vaccum desolderer, braid and a jewelers hand drill to clear out the holes to make it easier to get the new ones in.  I'm sure there other possibly easier ways but I chose the hard one.   I'm slightly better at desoldering now though :)


On Thu, Jan 24, 2019 at 06:24 AM, Raj vu2zap wrote:

Only three relays need to be replaced KT/1/2/3

Raj

At 24-01-19, you wrote:

I will also say you will have to perfect your desoldering skills to remove all 5 relays :)  I thought I knew how to desolder before I started... but clearly I was deluding myself.
I nearly gave up but watched a couple youtube video's and so someone much better than I doing it and managed to learn the way to do it with a simple suction vac and desoldering braid.. though I was really wishing I had one of those hakko electric vacuum desoldering tools :)



On Tue, Jan 22, 2019 at 06:55 PM, Dave Space wrote:
I actually did replace all of the relays with axicom relays.  I bought some parts to build an external filter to see how that does (not due to arrive for a while).  I'm transmitting SSB when doing the test.

I also bought the parts to replace L5 and L7 not due to arrive for a little while either.  Any chance the mod suggested for the v5 board would solve this harmonic?


Re: 2 New kits in stock!

Joel Fournol
 

Ok thank you David I'm waiting for your answer, I saw this support in a post with k8cec and the laserbeam over, it thanks joël f6cht.
Le 24/01/2019 à 20:18, N8DAH a écrit :

Joel,
 I will send you a email so we can sort it out. While this is not a item I stock we can work something out.
--
David

 N8DAH
Kit-Projects.com

Shop is open!


Re: Spurs/Harmonics fixes for v4 based on v5 board design?

Dave Space
 

Yep I just figured I would do the rest for good measure... though didn't realize how bad I was at desoldering.

To amend my previous statement it took vaccum desolderer, braid and a jewelers hand drill to clear out the holes to make it easier to get the new ones in.  I'm sure there other possibly easier ways but I chose the hard one.   I'm slightly better at desoldering now though :)


On Thu, Jan 24, 2019 at 06:24 AM, Raj vu2zap wrote:
Only three relays need to be replaced KT/1/2/3

Raj

At 24-01-19, you wrote:

I will also say you will have to perfect your desoldering skills to remove all 5 relays :)  I thought I knew how to desolder before I started... but clearly I was deluding myself.
I nearly gave up but watched a couple youtube video's and so someone much better than I doing it and managed to learn the way to do it with a simple suction vac and desoldering braid.. though I was really wishing I had one of those hakko electric vacuum desoldering tools :)



On Tue, Jan 22, 2019 at 06:55 PM, Dave Space wrote:
I actually did replace all of the relays with axicom relays.  I bought some parts to build an external filter to see how that does (not due to arrive for a while).  I'm transmitting SSB when doing the test.

I also bought the parts to replace L5 and L7 not due to arrive for a little while either.  Any chance the mod suggested for the v5 board would solve this harmonic?


Re: mike

Doug W
 

Martin,
Just to double check, the mic is just an electret mic like the picture below.  I don't have one in front of me to measure but it is approximately 10mm in diameter.




--
www.bitxmap.com


Re: mike

Curt
 

Martin

scrounge whatever hardware you can for assembly.  if you don't like this plan, there are several fine suppliers of cases aka enclosures available. 

if you have a 'surplus. electret based microphone - try it out.  I am using something once used with an HT I no longer have.  use a search engine here or on the web to see what others are using with the BITX.  Pacific Antenna in US has a microphone kit for these rigs - but its nothing you can't homebrew from the electret microphone furnished with the kit or available on ebay etc. 

do enjoy assembly of the fine rig.  the beauty is having it your own way as you assemble it, and a wealth of ideas from a world-wide community of builders. 

Curt


Re: Comprison

Curt
 

Lawrence

Good data!  Please notice that sensitivity relates to our ability to copy a signal in the background (and rig supplied) noise -- not how much audio the receiver can pump into the air.  yes I perceive you already agree. 

how a receiver changes with preamp on and off does vary with how gain is built into the receiver.  a receiver can be 'gain limited' - meaning more gain would improve sensitivity or 'noise limited' - which you can guess means more gain does not improve sensitivity. 

depending upon our latitude, season etc. the background noise does vary.  at lower HF there is more noise in the atmosphere than our receivers can make, this only changes at the upper part of the spectrum.  in a quiet area with little man-made noise it will be interesting to compare the uBITX to receivers having a preamp on 28 MHz.  I am expecting only a small difference, less than one S-unit maybe.

likely many already know this, but QRN is propagated via the ionosphere - often from tropical regions.  cool stuff!

73 Curt


mike

Martin KM6TCD
 

I've been admiring my bitx40 for a while, nice looking board.
Finally, I knuckled under to build it and found a couble of problems.
 
1. no mike.
 
2. One standoff has no threads - it happens.
    Furthermore, it could use about 2x as many standoffs. (The Radino should not be connected solely with ribon cable.)
 
What do I need to do?
 
m
78