Re: Harmonics and Relay Replacement

? will get you the relays at the cheapest price in the USA that I know of ?They even have free overnight shipping. ?

NO absolutely do NOT use a PC oven. ?You must use a solder sucker or solder braid from the underside of the board and unsolder each pin very carefully. In this case, using an oven would apply too much heat in all the wrong places with potentially disastrous results.

Not knowing your electronics background/expertise, my suggestion to you if you aren't comfortable with de-soldering the relays one pin at a time, ?you might try to find someone with de-soldering experience to help you so you don't accidentally destroy your uBITX PC board.

Jim, W0EB

Show quoted text

------ Original Message ------

From: "David Posthuma" <davep@...>

To: [email protected]

Sent: 10/12/2018 11:58:40 AM

Subject: Re: [BITX20] Harmonics and Relay Replacement

Jim:
?
What are the actual part numbers of the Axion relays and where are you ordering them from? Did you need to use a PCB oven to remove the relays? What was your technique? I’m sorry if these topics were already addressed and I missed it.
?
David A Posthuma, WD8PUO
1 (616) 283-7703
?
From: [email protected] <[email protected]> On Behalf Of Jim Sheldon
Sent: Friday, October 12, 2018 11:18 AM
To: [email protected]
Subject: Re: [BITX20] Harmonics and Relay Replacement
?
I have another V4 board that I'm going to build up, but I'm waiting on a special 3.2" Color TFT touch screen display (NOT a Nextion) for use with the Trimuvirate Skonk Worx "BITeensio" controller board. ?We have 2.8 and 5" displays running nicely with released software and instructions for them. ?The 5" draws too much current so the next is a compromise down to the 3.2" and that will probably be our last display iteration unless something really innovative comes out that's larger and keeps the current draw under 200 mA so we don't have to add heavy duty 3.3V regulators on the BITeensio.
?
I've already replaced the relays on the 3rd board with Axions (mounted on top) and I have one more set of the Axion relays on hand. ?I may just make up a test bed using a V3 board I have left over and keep it open frame with DIP sockets for the relays to make it easier to change them if something better than the Axion comes along. ?
?
One thing the Axions seemed to help with was reduce radiated pickup of digital noise from the controller card & wiring. ?It may be because I replace all 5 relays, or may be because I got better solder joints (non lead-free solder) when I replaced the relays.
?
Jim -- W0EB
?
------ Original Message ------
From: "Gary Anderson" <gary.ag5tx@...>
To: [email protected]
Sent: 10/12/2018 9:45:08 AM
Subject: Re: [BITX20] Harmonics and Relay Replacement
?
Good Morning Jim,
Thanks for entertaining the idea.? Your shared data maybe useful as you have shown same board and relay with different measured results.
For that particular board and the measurement data you gathered, I would say the results ARE encouraging from this viewpoint:
You have 4.5 dBc more margin to FCC spec on your worst case data point (40m 3rd harmonic) with the supplied data set.

Comments:
I have no measurement error / uncertainty reference or relevant personal judgement / experience to truly offer.
But, I would think it more difficult to accurately measure the case of more suppression, and so the uncertainty here would be higher.
Note that the 2nd and 3rd harmonics are swapping (80m Top and 17m Bot)

Regards,
Gary
AG5TX

Re: Harmonics and Relay Replacement

#60575

开云体育

Jim:

?

What are the actual part numbers of the Axion relays and where are you ordering them from? Did you need to use a PCB oven to remove the relays? What was your technique? I’m sorry if these topics were already addressed and I missed it.

?

David A Posthuma, WD8PUO

1 (616) 283-7703

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of Jim Sheldon
Sent: Friday, October 12, 2018 11:18 AM
To: [email protected]
Subject: Re: [BITX20] Harmonics and Relay Replacement

?

I have another V4 board that I'm going to build up, but I'm waiting on a special 3.2" Color TFT touch screen display (NOT a Nextion) for use with the Trimuvirate Skonk Worx "BITeensio" controller board. ?We have 2.8 and 5" displays running nicely with released software and instructions for them. ?The 5" draws too much current so the next is a compromise down to the 3.2" and that will probably be our last display iteration unless something really innovative comes out that's larger and keeps the current draw under 200 mA so we don't have to add heavy duty 3.3V regulators on the BITeensio.

?

I've already replaced the relays on the 3rd board with Axions (mounted on top) and I have one more set of the Axion relays on hand. ?I may just make up a test bed using a V3 board I have left over and keep it open frame with DIP sockets for the relays to make it easier to change them if something better than the Axion comes along. ?

?

One thing the Axions seemed to help with was reduce radiated pickup of digital noise from the controller card & wiring. ?It may be because I replace all 5 relays, or may be because I got better solder joints (non lead-free solder) when I replaced the relays.

?

Jim -- W0EB

?

------ Original Message ------

From: "Gary Anderson" <gary.ag5tx@...>

To: [email protected]

Sent: 10/12/2018 9:45:08 AM

Subject: Re: [BITX20] Harmonics and Relay Replacement

?

Good Morning Jim,
Thanks for entertaining the idea.? Your shared data maybe useful as you have shown same board and relay with different measured results.
For that particular board and the measurement data you gathered, I would say the results ARE encouraging from this viewpoint:
You have 4.5 dBc more margin to FCC spec on your worst case data point (40m 3rd harmonic) with the supplied data set.

Comments:
I have no measurement error / uncertainty reference or relevant personal judgement / experience to truly offer.
But, I would think it more difficult to accurately measure the case of more suppression, and so the uncertainty here would be higher.
Note that the 2nd and 3rd harmonics are swapping (80m Top and 17m Bot)

Regards,
Gary
AG5TX

Re: Simpler spur fix

#60574

In post? ? ?/g/BITX20/message/60519
Lawrence Galea pointed out a Hong Kong source for Axicom relays at $0.98 USD for quantity 1,
$0.60 USD for quantity 1000.?
If those are genuine, or perform as well as genuine, that might be a good source for HFSignals.

Jerry

Show quoted text

On Fri, Oct 12, 2018 at 06:47 AM, Raj vu2zap wrote:

The Axicom relays cost me about 5$ landed and taxed.. I am only going to change KT1,2,3 but in
production the cost has to be kept down in true BITX spirit.

Re: Harmonics and Relay Replacement

#60573

I have another V4 board that I'm going to build up, but I'm waiting on a special 3.2" Color TFT touch screen display (NOT a Nextion) for use with the Trimuvirate Skonk Worx "BITeensio" controller board. ?We have 2.8 and 5" displays running nicely with released software and instructions for them. ?The 5" draws too much current so the next is a compromise down to the 3.2" and that will probably be our last display iteration unless something really innovative comes out that's larger and keeps the current draw under 200 mA so we don't have to add heavy duty 3.3V regulators on the BITeensio.

I've already replaced the relays on the 3rd board with Axions (mounted on top) and I have one more set of the Axion relays on hand. ?I may just make up a test bed using a V3 board I have left over and keep it open frame with DIP sockets for the relays to make it easier to change them if something better than the Axion comes along. ?

One thing the Axions seemed to help with was reduce radiated pickup of digital noise from the controller card & wiring. ?It may be because I replace all 5 relays, or may be because I got better solder joints (non lead-free solder) when I replaced the relays.

Jim -- W0EB

Show quoted text

------ Original Message ------

From: "Gary Anderson" <gary.ag5tx@...>

To: [email protected]

Sent: 10/12/2018 9:45:08 AM

Subject: Re: [BITX20] Harmonics and Relay Replacement

Good Morning Jim,
Thanks for entertaining the idea.? Your shared data maybe useful as you have shown same board and relay with different measured results.
For that particular board and the measurement data you gathered, I would say the results ARE encouraging from this viewpoint:
You have 4.5 dBc more margin to FCC spec on your worst case data point (40m 3rd harmonic) with the supplied data set.

Comments:
I have no measurement error / uncertainty reference or relevant personal judgement / experience to truly offer.
But, I would think it more difficult to accurately measure the case of more suppression, and so the uncertainty here would be higher.
Note that the 2nd and 3rd harmonics are swapping (80m Top and 17m Bot)

Regards,
Gary
AG5TX

Re: Harmonics and Relay Replacement

#60572

Great find, Sarma, as the world continues to look into this problem.

I'll run a test later today with the 1mH inductor isolation of the relay coils and then see the effect of adding a 10nF capacitor across the coil. May be dependent on how the relay contact wiring is configured and what is on each armature. I wouldn't think there is a radiated problem between relays as he implies .....conducted, yes.

73 Kees K5BCQ?

Re: Harmonics and Relay Replacement

#60571

Good Morning Jim,
Thanks for entertaining the idea.? Your shared data maybe useful as you have shown same board and relay with different measured results.
For that particular board and the measurement data you gathered, I would say the results ARE encouraging from this viewpoint:
You have 4.5 dBc more margin to FCC spec on your worst case data point (40m 3rd harmonic) with the supplied data set.

Comments:
I have no measurement error / uncertainty reference or relevant personal judgement / experience to truly offer.
But, I would think it more difficult to accurately measure the case of more suppression, and so the uncertainty here would be higher.
Note that the 2nd and 3rd harmonics are swapping (80m Top and 17m Bot)

Regards,
Gary
AG5TX

Re: Harmonics and Relay Replacement

#60570

Thanks for those pictures, Sarma. To me, that seems to indicate even closer coupling from the relay armature to the coil. Bad for RF.

73 Kees K5BCQ

Re: Harmonics and Relay Replacement

Joe Puma

#60569

开云体育

This is a cool find. Nice read.?

Show quoted text

On Oct 12, 2018, at 6:49 AM, Mvs Sarma <mvssarma@...> wrote:

Regarding Filters and axicom realy towards band switching? , i saw an useful link.
?

Perhaps it helps.
regards
sarma
?vu3zmv

Re: Simpler spur fix

#60568

Sorry Owen,

Missed your reply.

I put the inductors in a convenient place without obliterating the component legends.

The seller on eBay had mentioned that they were Murata, the size may be 1210, slightly fatter than 1206.

Shielding the toroid made a slight change but this issue may be because of hi Q ringing. I just soldered them
as I saw fit and placed them at right angles to the toroid. That worked.. it also works in the exact place or
the old toroids.

Mike:

I think a combination of Q and small size and probably they are internally shielded I don't know.
I also replaced L1-4 with 330nH SMD and that helps a little on one test board.

My interest was to fix these problem with the simplest solution without major surgery. The next gen
board will probably be bigger with more inexpensive relays like two relays per filter.

The Axicom relays cost me about 5$ landed and taxed.. I am only going to change KT1,2,3 but in
production the cost has to be kept down in true BITX spirit.

Raj

At 12/10/2018, you wrote:

Show quoted text

I'd like to second this question about the required inductors. Is it that the SMD inductors have a lower Q, or is it the smaller physical size, or the change in position, or a combination of all these changes?

Thanks
Mike M.
KU4QO?

On Wed, Oct 10, 2018 at 12:01 PM ohwenzelph via Groups.Io <Ohwenzelph= [email protected]> wrote:

I like this, but...

looks like you left C215 in but took C211 out of the circuit, does it matter? Maybe not..

are you sure they are Murata? Are they shielded? Probably not exactly 1206, maybe 1210.

does shielding matter, does the self resonant frequency matter? If it works, I just want to be able to duplicate it!

thanks so much

Re: Simpler spur fix

#60567

I'd like to second this question about the required inductors. Is it that the SMD inductors have a lower Q, or is it the smaller physical size, or the change in position, or a combination of all these changes?

Thanks

Mike M.

KU4QO?

Show quoted text

On Wed, Oct 10, 2018 at 12:01 PM ohwenzelph via Groups.Io <Ohwenzelph=[email protected]> wrote:

I like this, but...

looks like you left C215 in but took C211 out of the circuit, does it matter? Maybe not..
are you sure they are Murata? Are they shielded? Probably not exactly 1206, maybe 1210.
does shielding matter, does the self resonant frequency matter? If it works, I just want to be able to duplicate it!
thanks so much
_._,_._,_

Re: Harmonics and Relay Replacement

#60566

Interesting link by this Italian guy, surely not a macaroni one hihi, he also says to add a capacitor across (?) the coil.

Show quoted text

Il 12/ott/2018 12:49, "Mvs Sarma" <mvssarma@...> ha scritto:

Regarding Filters and axicom realy towards band switching? , i saw an useful link.
?

Perhaps it helps.
regards
sarma
?vu3zmv

Re: Harmonics and Relay Replacement

#60565

Regarding Filters and axicom realy towards band switching? , i saw an useful link.
?

Perhaps it helps.
regards
sarma
?vu3zmv

Re: Harmonics and Relay Replacement

#60564

I had an old Panasonic DS2E relay. Here are top and side exploded photos. Sorry for lack of clarity

The contacts can be seen mounted on either side of the relay. The armature moves sideways pulling one and pushing another contact.
regards
sarma
?vu3zmv

DS2E TOPVIEW.jpg

DS2E SIDE VIEW.jpg

Re: Account issues

#60563

Turn off 2-Step Verification

Open your Google Account.
In the "Sign in & security" section, select 2-Step Verification. You might need to sign in.
Select Turn off.
A pop-up window will appear to confirm that you want to turn off 2-Step Verification. Select Turn off.

From the net!

Raj

At 12/10/2018, you wrote:

Show quoted text

I was using 2 factor authentication with Google. It is still set for my account, and I need to get it turned off. How do I contact a group admin or someone that can help fix my account?

Mike
AI4NS

--
Mike
AI4NS

Re: Recommended mods for spurs and harmonics

#60562

On Fri, Oct 12, 2018 at 09:06 AM, Jerry Gaffke wrote:

We do have insufficient local oscillator drive from CLK1 into the mixer,

Has anyone tried changing the attenuator from 6db to a 3db one?

73 NIck VK4PP

Re: Account issues

#60561

Mike? AI4NS

What is this "2-factor authentication with Google" that you mentioned?? I just looked at your

member profile on the BITX20 site and see nothing like that on Groups.io.? You are set for

All Messages, and Full Featured Digest.?

Arv? K7HKL

_._

Show quoted text

On Thu, Oct 11, 2018 at 5:13 PM Mike Short <ai4ns.mike@...> wrote:

I was using 2 factor authentication with Google. It is still set for my account, and I need to get it turned off. How do I contact a group admin or someone that can help fix my account?

Mike
AI4NS

--
Mike
AI4NS

Account issues

Mike Short

#60560

I was using 2 factor authentication with Google. It is still set for my account, and I need to get it turned off. How do I contact a group admin or someone that can help fix my account?

Mike

AI4NS

--
Mike
AI4NS

Recommended mods for spurs and harmonics

#60559

There were a bunch of spurs coming out of that first mixer into the 30mhz LPF on transmit that were below 30mhz.
One in particular (first flagged by Allison) was at? (45mhz - Carrier), so transmitting at 21mhz
we got a spur at 45-21=24mhz.

Some of the spurs were be due to unwanted coupling from the power amp back into that 45mhz IF.
This issue is possibly addressed by Raj's hack at L5 and L7:??
? ??/g/BITX20/message/60453

Raj previously had some success with adding a second 45mhz crystal filter,
but it's looking like the L5,L7 hack may be a better solution.
? ??/g/BITX20/topic/25208658

The four relay switched transmit LPF's do not attenuate harmonics as well as they should,
as first pointed out by Warren.
Many have addressed this with major hacks to the uBitx board, or by adding external filters
in line with the antenna.? But it is now looking like this can be adequately addressed (except 40m)
by simply replacing the relays with the Axicom, which is more suitable for switching RF:
? ??/g/BITX20/message/60368
With luck, 40 meters can also be cleaned up with a minor mod to the board traces
while swapping out the relays.
Kees is looking at various ways of improving the performance of the existing relays,
if it works this may be easier and cheaper than replacing the relays:
? ??/g/BITX20/topic/27240335

We do have insufficient local oscillator drive from CLK1 into the mixer,
and the related issue of too much signal coming in from the 45mhz IF.
That will contribute intermodulation distortion.
Also more carrier leakage than we should have.
However these issues are close in to the transmitted signal, within the bandwidth
used by a typical AM signal, and generally not a problem with regard to regulations.

Yet another issue is inadequate power out on the high bands, such as 10 meters.
Addressing this is perhaps best left for v5 of the uBitx, or perhaps grafting G0UPL's
new QSX power amp to the uBitx:??/g/BITX20/topic/27121196
We need to have a clean signal before we worry about making it stronger.

Some are using high power external linear amps with the uBitx.
Not a good idea unless you first clean up the spurs, harmonics, IMD,
and carrier leakage described here.?

Between Raj's L5,L7 fix and cleaning up the relays around the transmit LPF's,
the uBitx may be good enough to meet regs across all bands and all modes.
Both of these fixes are starting to look cheap and easy enough to do.
But unless you are the adventurous sort, I suggest holding back a few weeks
till further reports are in.

Jerry, KE7ER

Show quoted text

On Thu, Oct 11, 2018 at 02:11 PM, ajparent1/KB1GMX wrote:

Did You make a measurement on the mirror reception which should be attenuated by the input lpf? Or is it another stone to be lifted?

A low pass filter at the input of Q90 is insufficient to remove anything below its cut of of about 33.5mhz.
This is not new new here, I just haven't mentioned it in the last 4 weeks, prior to that it was a near daily topic
so its gone to the collective forgetfulness.

Problem 11.996(approx) carrier osc leakage.? Board level issue with OSC0 propagation to other parts of the board.

Problem? mirror image of output and IF, spectral folding from mixing products and sampling theory.? Side effect of?
insufficient filtering results in spurs in the 16-17mhz range when tuned to 10M SSB.? The only way to filter that is
bandpass at the output of the mixer.

>>>>in the QRP-labs PA : the output stage fo the driver is using a center tapped transformer. Why not choose an extra bifilar wound choke as correctly done int the PA stage?? Did You try this configuration? <<<

Ask Hans but the design for that stage is low power so current effects in the transformer are minimal at that
power level.? ? In my work I'e done both and for that stage and power level its overkill.
?
Allison

Re: Spurs and Harmonics

#60558

OK, 3 more plots.? Mouser just delivered. The first one is with 680uH and the second is with 1mH. That's about 8dB better at 25MHz and below when compared to a plain uBITX "16 pin" relay.

The third plot shows a plain "16 pin" HFD-27 relay for comparison with no inductance added to the coil leads.

73 Kees K5BCQ

Re: QSX 10W HF Linear PA kit

#60557

On Thu, Oct 11, 2018 at 01:05 PM, Henning Weddig wrote:
Did You make a measurement on the mirror reception which should be attenuated by the input lpf? Or is it another stone to be lifted?

A low pass filter at the input of Q90 is insufficient to remove anything below its cut of of about 33.5mhz.
This is not new new here, I just haven't mentioned it in the last 4 weeks, prior to that it was a near daily topic
so its gone to the collective forgetfulness.

Problem 11.996(approx) carrier osc leakage.? Board level issue with OSC0 propagation to other parts of the board.

Problem? mirror image of output and IF, spectral folding from mixing products and sampling theory.? Side effect of?
insufficient filtering results in spurs in the 16-17mhz range when tuned to 10M SSB.? The only way to filter that is
bandpass at the output of the mixer.

>>>>in the QRP-labs PA : the output stage fo the driver is using a center tapped transformer. Why not choose an extra bifilar wound choke as correctly done int the PA stage?? Did You try this configuration? <<<

Ask Hans but the design for that stage is low power so current effects in the transformer are minimal at that
power level.? ? In my work I'e done both and for that stage and power level its overkill.
?
Allison