Date   

Re: Power meter J1

Jerry Haigwood
 

Hi Will,

    Jim and I have several products in the pipeline we are working on.  In fact, I tend to jump ahead sometimes and have to be reeled back in.  While we can’t say much about these efforts just yet, we will announce them when they are ready for prime time.  Stick with us and you will have fun building stuff and end up with some useful test equipment/radio gadgets.

Jerry W5JH

"building something without experimenting is just solder practice"

 

From: PHSNA@... [mailto:PHSNA@...] On Behalf Of Will
Sent: Wednesday, November 06, 2013 3:18 PM
To: PHSNA@...
Subject: Re: [PHSNA] Power meter J1

 

 

Thanks for that info, Jim.

I was wondering how it was done, didn't seem to be a pc layout for a socket on the board.  I was waiting for board to arrive to confirm. The toroids I ordered from Diz have arrived. They were sent only a few days before boards were posted.

Any thoughts as to next project?

How about LC meter with different frequencies?  and/or Q meter.  There are most of the basics of them in the Arduino/AD8950 combo.

Cheers
Will
ZL1TAO

> ----- Original Message -----
> From: n5ib@...
> Sent: 11/07/13 02:16 AM
> To: PHSNA@...
> Subject: Re: [PHSNA] Power meter J1
>
> On Tue, 5 Nov 2013 20:01:30 -0800 "Jim Pruitt" <wa7duy@...>
> writes:
> What are builders using for J1, rf input, for the power meter? Or are
> you just hooking the coax directly? I had wanted to use a SNB connector
> there but get the impression that most do not use a jack there at all. I
> like to use interconnects rather than hooking cables directly and wonder
> what others do in that situation.
>
> -----snip------
>
> A short piece of RG174 from the board to a chassis-mounted connector.
>
> Most folks no doubt will use a BNC. If you do be sure to use the kind
> that grounds the shell with the mounting hardware. There are some that
> have an insulating sleeve that leaves both terminals floating. Then you
> have to ground the shield terminal separately, and it's not as RF tight.
>
> Notice that there are two grounded pads on either side of the RF input
> pad, and they have larger diameter holes. My scheme is to tease the braid
> into two strands to solder on either side. Another, mechanically more
> secure, method is to fold the braid back over the outer jacket, loop some
> hookup wire once around and solder the wire to the pads and the braid.
> I'll take a picture of that to add to the photo shoot.
>
> A good quality RCA jack would be OK (It was good enough for Collins
> Radio, I believe)
> I flirted with the temptation to use an SMA, since I have some SMA
> attenuators, fittings, and terminators with my TAPR/TenTec VNA.
>
> Bringing the A/D signal out can be done with another BNC/RCA/SMA. Or as
> other have suggested, a feed-through capacitor. And as Jerry said, he has
> success with a pin jack (bypassed at the box wall).
>
> Jim, N5IB


Re: Scalar Network Analyzer vs Wobbulator

Graham <planophore@...>
 


very cool Tom.

I have had a similar thought, in fact there are adapter boards to allow you to use arduino shields on the PI.

<http://www.cooking-hacks.com/documentation/tutorials/raspberry-pi-to-arduino-shields-connection-bridge>

for anyone who might be interested.

While I like the PI I am also a big fan of the BeagleBoard Black, kind of like the PI on steroids. Interestingly there is also an adapter "cape" for the Beableboard and BeagleBoard Black that lets them emulate the GPIO connector of the PI, AB Electronics in the UK



for anyone who might be interested.

This last item brings the compatibility of the PI and the BeagleBone Black closer together and makes them more complimentary than competitors, at least to my way of thinking.

I have two sets of the PHSNA boards and my thinking is I will build one and use on an Arduino as intended and adapt the other for use on a PI or BeagleBone.

I have signed up for your new group and I am now off to have a good thorough read of your blog.

cheers, Graham ve3gtc


On 13-11-06 10:45 AM, asliceofraspberrypi@... wrote:
 

Hi everyone,


A friend of mine told me about this group, because I have been involved in doing something very similar, and I think maybe it would be useful to exchange ideas.

My project is a Raspberry Pi Wobulator, which is effectively the same as the PHSNA, except it uses a Raspberry Pi, and a rather hastily designed and built buffer amp/detector stage. My project also uses a AD9850 based DDS module to generate the RF, and an "off-the-shelf" ADC module (based on the MCP3424 chip) to measure the response of the circuit under test.

If anyone is interested full details of the Raspberry Pi Wobbulator are on my blog:


The design, construction, software development and testing are all covered if you look back through the blog posts.

... and I've set up a Yahoo group for it as well called "rpiwobbulator"

I hope to develop the Raspberry Pi Wobbulator into a simple plug-in module for the Raspberry Pi.

73 de Tom MI0IOU


Re: Power meter J1

William Kimber
 

Thanks for that info, Jim.

I was wondering how it was done, didn't seem to be a pc layout for a socket on the board.  I was waiting for board to arrive to confirm. The toroids I ordered from Diz have arrived. They were sent only a few days before boards were posted.

Any thoughts as to next project?

How about LC meter with different frequencies?  and/or Q meter.  There are most of the basics of them in the Arduino/AD8950 combo.

Cheers
Will
ZL1TAO

----- Original Message -----
From: n5ib@...
Sent: 11/07/13 02:16 AM
To: PHSNA@...
Subject: Re: [PHSNA] Power meter J1

On Tue, 5 Nov 2013 20:01:30 -0800 "Jim Pruitt" <wa7duy@...>
writes:
What are builders using for J1, rf input, for the power meter? Or are
you just hooking the coax directly? I had wanted to use a SNB connector
there but get the impression that most do not use a jack there at all. I
like to use interconnects rather than hooking cables directly and wonder
what others do in that situation.

-----snip------

A short piece of RG174 from the board to a chassis-mounted connector.

Most folks no doubt will use a BNC. If you do be sure to use the kind
that grounds the shell with the mounting hardware. There are some that
have an insulating sleeve that leaves both terminals floating. Then you
have to ground the shield terminal separately, and it's not as RF tight.

Notice that there are two grounded pads on either side of the RF input
pad, and they have larger diameter holes. My scheme is to tease the braid
into two strands to solder on either side. Another, mechanically more
secure, method is to fold the braid back over the outer jacket, loop some
hookup wire once around and solder the wire to the pads and the braid.
I'll take a picture of that to add to the photo shoot.

A good quality RCA jack would be OK (It was good enough for Collins
Radio, I believe)
I flirted with the temptation to use an SMA, since I have some SMA
attenuators, fittings, and terminators with my TAPR/TenTec VNA.

Bringing the A/D signal out can be done with another BNC/RCA/SMA. Or as
other have suggested, a feed-through capacitor. And as Jerry said, he has
success with a pin jack (bypassed at the box wall).

Jim, N5IB


Re: Power meter J1

N5IB
 

On Tue, 5 Nov 2013 20:01:30 -0800 "Jim Pruitt" <wa7duy@...> writes:
What are builders using for J1, rf input, for the power meter?  Or are you just hooking the coax directly?  I had wanted to use a SNB connector there but get the impression that most do not use a jack there at all.  I like to use interconnects rather than hooking cables directly and wonder what others do in that situation.
 
-----snip------
 
A short piece of RG174 from the board to a chassis-mounted connector. 
 
Most folks no doubt will use a BNC. If you do be sure to use the kind that grounds the shell with the mounting hardware. There are some that have an insulating sleeve that leaves both terminals floating. Then you have to ground the shield terminal separately, and it's not as RF tight.
 
Notice that there are two grounded pads on either side of the RF input pad, and they have larger diameter holes. My scheme is to tease the braid into two strands to solder on either side. Another, mechanically more secure, method is to fold the braid back over the outer jacket, loop some hookup wire once around and solder the wire to the pads and the braid. I'll take a picture of that to add to the photo shoot.
 
A good quality RCA jack would be OK (It was good enough for Collins Radio, I believe)
I flirted with the temptation to use an SMA, since I have some SMA attenuators, fittings, and terminators with my TAPR/TenTec VNA.
 
Bringing the A/D signal out can be done with another BNC/RCA/SMA. Or as other have suggested, a feed-through capacitor. And as Jerry said, he has success with a pin jack (bypassed at the box wall).
 
Jim, N5IB
 
 
 
 


Re: BUILDER ALERT!! - SSNA - D1 - ALERT

N5IB
 

I've just now gotten time to begin with the PHSNA build.  On the ERA-3+ board, the D1 pad is NOT connected to the ground plane.  The fine connecting traces only continue part way to the pad from ground.  I've studied the board under high magnification and confirmed the lack of ground connection with a continuity tester.
 
---------snip-----------
 
Mike's right. I just examined my several boards and verified that the pad IS grounded on the top side on the 5109 version but NOT on the ERA version. The little grounding tendrils look like they got started but didn't close the deal. This gets curiouser and curiouser. I'm going to spend a little quality time with a microscope this morning and check other pads that are supposed to be grounded.
 
Given the reduced clearance margin around the pads, the possibility of a solder bridge remains high, and that pad is right on the power bus. So I'd recommend that you still treat it like an extraneous ground and use the fix detailed in the Builder Alert.
 
Jim, N5IB
 
 


Scalar Network Analyzer vs Wobbulator

Tom Herbison
 

Hi everyone,


A friend of mine told me about this group, because I have been involved in doing something very similar, and I think maybe it would be useful to exchange ideas.

My project is a Raspberry Pi Wobulator, which is effectively the same as the PHSNA, except it uses a Raspberry Pi, and a rather hastily designed and built buffer amp/detector stage. My project also uses a AD9850 based DDS module to generate the RF, and an "off-the-shelf" ADC module (based on the MCP3424 chip) to measure the response of the circuit under test.

If anyone is interested full details of the Raspberry Pi Wobbulator are on my blog:

www.asliceofraspberrypi.co.uk

The design, construction, software development and testing are all covered if you look back through the blog posts.

... and I've set up a Yahoo group for it as well called "rpiwobbulator"

I hope to develop the Raspberry Pi Wobbulator into a simple plug-in module for the Raspberry Pi.

73 de Tom MI0IOU


Re: Power meter J1

Jerry Haigwood
 

Hi Jim,

   The power meter must be built into a shielded box.  The circuit is so sensitive that it picks up stray RF.  Just turning mine on causes the meter to register a power level.  It cannot be built into the same box as the SSNA or things will not function correctly.  Therefore, I used a BNC connector for the RF input.  The power supply is an internal 9V battery to prevent RF from coming in on the DC lines.  It is a good idea to also shield the back of the analog meter.  For DC output, I used Tip jacks.  However, another BNC might be good also.

Jerry W5JH

"building something without experimenting is just solder practice"

 

From: PHSNA@... [mailto:PHSNA@...] On Behalf Of Jim Pruitt
Sent: Tuesday, November 05, 2013 10:02 PM
To: PHSNA@...
Subject: [PHSNA] Power meter J1

 

 

What are builders using for J1, rf input, for the power meter?  Or are you just hooking the coax directly?  I had wanted to use a SNB connector there but get the impression that most do not use a jack there at all.  I like to use interconnects rather than hooking cables directly and wonder what others do in that situation.

 

Thank you.

 

Jim Pruitt

WA7DUY


Re: BUILDER ALERT!! - SSNA - D1 - ALERT

Michael McShan <n5jky@...>
 

I've just now gotten time to begin with the PHSNA build.  On the ERA-3+ board, the D1 pad is NOT connected to the ground plane.  The fine connecting traces only continue part way to the pad from ground.  I've studied the board under high magnification and confirmed the lack of ground connection with a continuity tester.

FYI,
Mike N5JKY
OK City

On Oct 31, 2013, at 8:22 PM, n5ib@... wrote:

Y'all thank Nick... he found another one... this one's mysterious. The anode end of D1 is clearly connected to the ground plane on the top side. On the bottom side the layout doesn't show a ground plane connection, but the margin around the pad is reduced. Both conditions are in error. The layout file ended up showing BOTH a clearance margin and a filled plane connection. Don't know how that could happen.

Here's the fix...
Connect and solder the left (non-banded) lead of  D1 and the right lead of F1 together as "flying leads", but DO NOT solder them  to the PC pads.  Leave them elevated above the board. If you choose to not use F1 at all, you can just connect D1 from its normal banded-end pad to the left pad of F1, skipping the two middle pads entirely.

Once again, when I get home I'll post a photo.

Jim, N5IB



Power meter J1

Jim Pruitt <wa7duy@...>
 

What are builders using for J1, rf input, for the power meter?  Or are you just hooking the coax directly?  I had wanted to use a SNB connector there but get the impression that most do not use a jack there at all.  I like to use interconnects rather than hooking cables directly and wonder what others do in that situation.
 
Thank you.
 
Jim Pruitt
WA7DUY


Power Meter Build Photos (SOIC)

N5IB
 

I've posted a photo album with the first few pics of the SOIC version power meter under construction. Especially note the detail of the inductor L1.

Jim, N5IB


Re: Some initial testing & success

N5IB
 


On 05 Nov 2013 06:20:29 -0800 <j.b.hall@...> writes:
Mine is now generating a signal so I will move on to the filter and amp section.
The AD8950 runs a little warm but I guess that is normal.
------------------------------snip--------------------------
 
My 9850 module is running on 3.3 V. That reduces the current demand a bit and thus the heat. The 3.3 V regulator sees a bit higher voltage drop across it than the 5 V would, but the reduced current makes it about an even trade. Even though that's just ouside the munufacturer's published envelope for the 125 MHz clock it seems to work fine.
 
If you do that, you'll need to replace the 7805 with a TO-220 packaged 3.3 V regulator, then leave jumper JP1 open. You can also omit the fuse F2.
You'll now supply power to the Arduini via its USB port.
I wondered a bit about mixing the 3.3V DDS with the 5 V Arduino, but I haven't smoked anything yet.
As always, caveat molitor  i.e., YMMV
 
Jim, N5IB
 
 


Re: Some initial testing & success

W0PWE
 

Hey Nick - Thanks for the note about the jumpers on the DDS board. That saved me a lot of head scratching. 


Mine is now generating a signal so I will move on to the filter and amp section. The AD8950 runs a little warm but I guess that is normal. 

73 - Jerry - W0PWE 



---In phsna@..., <planophore@...> wrote:

Just as the subject line says, found in todays mail.

Boards look mighty fine and I am keeping notes on the two minor problems
so far reported on list.


cheers, Graham ve3gtc


Re: SSNA Power Options

N5IB
 

I allowed for several options for powering the system just for convenience, depending on what other accessories folks might be tagging on.
 
A) I think the simplest way is to supply 12 V to the SSNA board and let the on board 5 V regulator power the Arduino and the DDS. A total of about 150 MA is needed from a 12 V supply.
When the Arduino is plugged into the USB port of the PC that USB port will only need to supply a couple of mA.
 
B) If you're worried about heat in the SSNA's regulator you could let the USB port supply 5 V power to the Arduino. It will draw around 50 mA
Then connect 12 V to the SSNA board, whose 5 V regulator now need only power the DDS, needing around 100 mA
I actually used this mode on the first prototype, so I could use a 3.3 V regulator instead of the 7805 to power the DDS, which appears to work fine.
 
C) You could also supply 12 V (the full 150 mA needed) directly to the Arduino's coax power jack, which would use its own 5 V regulator for itself, and then the 12 V would be routed to the SSNA for use by it and the DDS.
 
Bottom line... I'd go for "A"
 
Use "B" if you want to try the 3.3 V on the DDS
 
Jim, N5IB
 
On Mon, 4 Nov 2013 09:29:35 -0800 (PST) Don Lewis <dlewis11193@...> writes:

Jim,
There are several power options available for hook-up on the SSNA board.
Which one will provide the best service?
What did you have in mind when you designed them in


Re: LM7805 and LM317L on SSNA

N5IB
 

New schematic and layout PDF files are posted.

COMBO 2N5109 Schematic and Layout.pdf
COMBO ERA3 Schematic and Layout.pdf

No substantive changes, just cleaning up some notation issues y'all have uncovered.

If you haven't yet, be sure to retrieve the Builder Alert PDF file

Jim, N5IB


Re: LM7805 and LM317L on SSNA

Gene Dorcas <gene@...>
 

.  .  and, speaking of parts.  I couldn’t afford a high0quality Simpson panel meter for the power meter but found a 1ma meter at Electronic Goldmine for $21.00.  The comparable Simpson is $88.00.  Recently Electronic Goldmine had them on sale for $10.00. I bought 3 of them.

 

From: PHSNA@... [mailto:PHSNA@...] On Behalf Of n5ib@...
Sent: Monday, November 04, 2013 6:30 AM
To: PHSNA@...
Subject: [PHSNA] LM7805 and LM317L on SSNA

 

 

The numbered pins on the schematic are, uhhhmmm, "unconventional'  :^))  
But in the case of the LM7805 they properly match the PCB layout, so the part is correctly installed according to the silk-screened outline.

The issue with the LM317L is addressed in the Builder Alert PDF file that's posted.

Much like the admonition to Dorothy, "Pay no attention to those pin numbers behind that curtain!"

I'll clean that up later and make sure they conform to data sheet conventions. Then I'll hide the blessed numbers so they won't haunt me again  :^))

Jim, N5IB



Same


LM7805 and LM317L on SSNA

N5IB
 

The numbered pins on the schematic are, uhhhmmm, "unconventional'  :^))  
But in the case of the LM7805 they properly match the PCB layout, so the part is correctly installed according to the silk-screened outline.

The issue with the LM317L is addressed in the Builder Alert PDF file that's posted.

Much like the admonition to Dorothy, "Pay no attention to those pin numbers behind that curtain!"

I'll clean that up later and make sure they conform to data sheet conventions. Then I'll hide the blessed numbers so they won't haunt me again  :^))

Jim, N5IB



Same


Re: BUILDER ALERT!! - SSNA - D1 - ALERT

Don Lewis
 

Same for LM317, also, ...I believe.  On the schematic.
 
Is pinout standard notation?  Please check.
 
Thanks, ...-Don
 
 
 
 
 

From: Paul Schumacher To: "PHSNA@..."
Sent: Sunday, November 3, 2013 9:30 PM
Subject: Re: [PHSNA] BUILDER ALERT!! - SSNA - D1 - ALERT

 
Pins 1 and 2 are reversed on the schematic, but I believe they are correct on the board.   Paul, K0ZYV


On Sunday, November 3, 2013 7:22 PM, Don Lewis wrote:
 
Jim:
 
Is the pinout on the schematic correct for the 7805 regulator?
 
-Don
 
 
 

From: "n5ib@..." To: PHSNA@...
Sent: Thursday, October 31, 2013 8:22 PM
Subject: [PHSNA] BUILDER ALERT!! - SSNA - D1 - ALERT

 
Y&apos;all thank Nick... he found another one... this one&apos;s mysterious. The anode end of D1 is clearly connected to the ground plane on the top side. On the bottom side the layout doesn&apos;t show a ground plane connection, but the margin around the pad is reduced. Both conditions are in error. The layout file ended up showing BOTH a clearance margin and a filled plane connection. Don&apos;t know how that could happen.

Here&apos;s the fix...
Connect and solder the left (non-banded) lead of  D1 and the right lead of F1 together as "flying leads", but DO NOT solder them  to the PC pads.  Leave them elevated above the board. If you choose to not use F1 at all, you can just connect D1 from its normal banded-end pad to the left pad of F1, skipping the two middle pads entirely.

Once again, when I get home I&apos;ll post a photo.

Jim, N5IB







Re: BUILDER ALERT!! - SSNA - D1 - ALERT

Paul Schumacher
 

Pins 1 and 2 are reversed on the schematic, but I believe they are correct on the board.   Paul, K0ZYV


On Sunday, November 3, 2013 7:22 PM, Don Lewis wrote:
 
Jim:
 
Is the pinout on the schematic correct for the 7805 regulator?
 
-Don
 
 
 

From: "n5ib@..."
To: PHSNA@...
Sent: Thursday, October 31, 2013 8:22 PM
Subject: [PHSNA] BUILDER ALERT!! - SSNA - D1 - ALERT

 
Y&apos;all thank Nick... he found another one... this one&apos;s mysterious. The anode end of D1 is clearly connected to the ground plane on the top side. On the bottom side the layout doesn&apos;t show a ground plane connection, but the margin around the pad is reduced. Both conditions are in error. The layout file ended up showing BOTH a clearance margin and a filled plane connection. Don&apos;t know how that could happen.

Here&apos;s the fix...
Connect and solder the left (non-banded) lead of  D1 and the right lead of F1 together as "flying leads", but DO NOT solder them  to the PC pads.  Leave them elevated above the board. If you choose to not use F1 at all, you can just connect D1 from its normal banded-end pad to the left pad of F1, skipping the two middle pads entirely.

Once again, when I get home I&apos;ll post a photo.

Jim, N5IB





Re: BUILDER ALERT!! - SSNA - D1 - ALERT

Don Lewis
 

Jim:
 
Is the pinout on the schematic correct for the 7805 regulator?
 
-Don
 
 
 

From: "n5ib@..."
To: PHSNA@...
Sent: Thursday, October 31, 2013 8:22 PM
Subject: [PHSNA] BUILDER ALERT!! - SSNA - D1 - ALERT

 
Y&apos;all thank Nick... he found another one... this one&apos;s mysterious. The anode end of D1 is clearly connected to the ground plane on the top side. On the bottom side the layout doesn&apos;t show a ground plane connection, but the margin around the pad is reduced. Both conditions are in error. The layout file ended up showing BOTH a clearance margin and a filled plane connection. Don&apos;t know how that could happen.

Here&apos;s the fix...
Connect and solder the left (non-banded) lead of  D1 and the right lead of F1 together as "flying leads", but DO NOT solder them  to the PC pads.  Leave them elevated above the board. If you choose to not use F1 at all, you can just connect D1 from its normal banded-end pad to the left pad of F1, skipping the two middle pads entirely.

Once again, when I get home I&apos;ll post a photo.

Jim, N5IB



Re: Building the power meter

N5IB
 

New Power Meter schematic is posted. It matches the PCB layouts rev 1.20 and rev1.25.

Just to recap, the previously posted schematic went with the "chubby" version of the PC board that I'd prototyped. When I laid out the "skinny" version to piggy back on the SSNA board, I eliminated the capacitor at C5 since it was very near C4 and was just there for bypassing.

The C5 part ID was reassigned to the capacitor near P2 and P3, which bypasses the DC output heading towards the SSNA. As Garey said, that cap on the PCB is NOT sufficient bypassing, its just there for "langiappe."

Either bring the DC signal out via a feed-thru cap, or use a shielded connector like a BNC or RCA and bypass i either .1 or .01 right at the connector body.

Jim, N5IB