Date   

#ubitx Digital & Audio 8 pin connectors #ubitx

Jim Sheldon
 

Anyone know where (in the US) I can find those connectors (female) and the crimp on pins?

I need to make up some of those connectors to wire up test connections to a Raduino so I can test the CW stuff without actually keying the radio.

Jim - W0EB


Re: AE7EU Top Level PCB Mod

Jerry Gaffke
 

Regarding putting diodes near the front end of the uBitx, this post is worth reviewing:
    https://groups.io/g/BITX20/message/35656
And this thread, which continues the discussion:
    https://groups.io/g/BITX20/message/37330

So that ADE-1 attenuator might work better if placed after the 45mhz roofing filter, or somewhere beyond that.
But up front where we have the whole world of RF coming in, the diodes may create harmonics
of a 50kW AM broadcast station across town, harmonics that will show up in the ham bands.

Vince wrote: "Before smoothing, at moderately high RF fields the RF was setting off the Halon alarm!"

Exactly what do you mean by "smoothing"?
Do you figure the diode ring mixer was creating harmonics?

Jerry, KE7ER

On Fri, Jan 12, 2018 at 10:38 pm, Diver Martin wrote:
This is one of those "We'll see how this works" things I think.  The guy who I've been talking to knows his stuff pretty well when it comes to building radios, so I trust his advice.  He's got some cool stuff on his webpage, though he doesn't sell any of the kits anymore I think.... http://www.gridtoys.com.
 


Re: Bitx40/Raduino no power - help

Vic WA4THR
 

Yes, thanks Raj. I was confusing the pot numbers...I was adjusting RV1 not RV136. Found the problem to be a dead Q13, which seems to happen a lot!

=Vic=


Re: Sotabeams CW filter problem

Bob Benedict, KD8CGH
 

I tried the 90.1 uF cap in series with the AF filter output but it didn't help.
My filter is always on, but there is no noise from it when it is bypassed, so I don't think it is generating noise on the power line.
    Bob   KD8CGH


Re: Micro-BITX ... Lost in post ? Possibly

Dave Bottom <ars.kd6az@...>
 

Apparently that number is the board number as tested from the run or #71 of Run 1.  Yours ordered on Dec 9th while mine ordered on Dec 10th was something like #322/1.  
They were certainly cranking them out like that for just a few days before using up the entire first run.  

Congrats and keep the soldering iron warm.


Dave Wi6R


On Thu, Jan 11, 2018 at 11:55 AM, G1KQH via Groups.Io <g1kqh@...> wrote:
Mine arrived today too!


You just got to find the inner strength to wait!


73 Steve




--
73 Dave WI6R


Re: AE7EU Top Level PCB Mod

Mike Woods
 

Ok - found a circuit on this group that removes my confusion. 

 You have it wired correctly Martin!

The data sheet is not very clear with nomenclature - if the PIN numbers were indicated on the circuit diagram then it would be far less confusing!

Mike


On Sat, 13 Jan 2018 at 8:42 PM, Mike Woods <mhwoods@...> wrote:
We agree that we need to inject the DC into pin I in the circuit (the centre tap on the transformer).  I believe this is pin 6 (LO) for port I and not pin 2 (IF).  In your circuit diagram you have LO pin 6 connected to the antenna and not to the DC input.  Sorry I wasn’t clear,  but I think there may be an error.  The data sheet confuses the matter because different nomenclature is used in the circuit diagram from the pinout on the chip.  I believe the labels correspond as follows: L = RF, I=LO, and R=IF.  But I may be wrong!  I have not used this package before.

Mike

On Sat, 13 Jan 2018 at 6:43 PM, Diver Martin <diver.martin@...> wrote:
Hi Mike,

Check out the datasheet for the ADE-1 here: https://www.minicircuits.com/pdfs/ADE-1.pdf .  Page 1, bottom right side for the electrical schematic, you'll see the "I" pin has a DC connection to the diodes and then to ground.  This will forward-bias two of the diodes, and reverse-bias the other two.  A current limiting resistor (R14 in this case) limits the current going through the diodes.  I picked 1.2k randomly, it might be 1k-100k, I'll have to play with it I'm sure.

On Fri, Jan 12, 2018 at 9:21 PM, Mike Woods <mhwoods@...> wrote:
Ok - I understand how it works now.  The one remaining question is how injecting DC into the output side (IF pin) of the mixer (as you have it drawn) would unbalance the mixer? Doesn’t this look like a short circuit to the DC? I would have thought you would connect the DC to the LO input to have current flowing through the diodes?

Mike 




--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?


Re: AE7EU Top Level PCB Mod

Mike Woods
 

We agree that we need to inject the DC into pin I in the circuit (the centre tap on the transformer).  I believe this is pin 6 (LO) for port I and not pin 2 (IF).  In your circuit diagram you have LO pin 6 connected to the antenna and not to the DC input.  Sorry I wasn’t clear,  but I think there may be an error.  The data sheet confuses the matter because different nomenclature is used in the circuit diagram from the pinout on the chip.  I believe the labels correspond as follows: L = RF, I=LO, and R=IF.  But I may be wrong!  I have not used this package before.

Mike


On Sat, 13 Jan 2018 at 6:43 PM, Diver Martin <diver.martin@...> wrote:
Hi Mike,

Check out the datasheet for the ADE-1 here: https://www.minicircuits.com/pdfs/ADE-1.pdf .  Page 1, bottom right side for the electrical schematic, you'll see the "I" pin has a DC connection to the diodes and then to ground.  This will forward-bias two of the diodes, and reverse-bias the other two.  A current limiting resistor (R14 in this case) limits the current going through the diodes.  I picked 1.2k randomly, it might be 1k-100k, I'll have to play with it I'm sure.

On Fri, Jan 12, 2018 at 9:21 PM, Mike Woods <mhwoods@...> wrote:
Ok - I understand how it works now.  The one remaining question is how injecting DC into the output side (IF pin) of the mixer (as you have it drawn) would unbalance the mixer? Doesn’t this look like a short circuit to the DC? I would have thought you would connect the DC to the LO input to have current flowing through the diodes?

Mike 




--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?


Re: AE7EU Top Level PCB Mod

Diver Martin <diver.martin@...>
 

This is one of those "We'll see how this works" things I think.  The guy who I've been talking to knows his stuff pretty well when it comes to building radios, so I trust his advice.  He's got some cool stuff on his webpage, though he doesn't sell any of the kits anymore I think.... http://www.gridtoys.com.

On Fri, Jan 12, 2018 at 10:26 PM, Vince Vielhaber <vev@...> wrote:


On 01/13/2018 12:56 AM, Jerry Gaffke via Groups.Io wrote:
A neat trick, I've never seen a mixer used as an attenuator.
Though might be cheaper ways than using an ADE-1
And I'm curious how linear this would be for incoming high level RF signals
when partially attenuated.

Amplifier Research Model 777 is an RF leveling preamp.  It uses a mini-circuits mixer as an attenuator.  First time I saw one used for that. I had to modify one to smooth the output.  It was in the chain between an RF generator and an amplifier putting RF into an anechoic chamber.  Before smoothing, at moderately high RF fields the RF was setting off the Halon alarm!

Vince.
--
  Michigan VHF Corp.   http://www.nobucks.net/   http://www.CDupe.com/
                          http://www.metalworkingfun.com






--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?


Re: AE7EU Top Level PCB Mod

Vince Vielhaber
 

On 01/13/2018 12:56 AM, Jerry Gaffke via Groups.Io wrote:
A neat trick, I've never seen a mixer used as an attenuator.
Though might be cheaper ways than using an ADE-1
And I'm curious how linear this would be for incoming high level RF signals
when partially attenuated.
Amplifier Research Model 777 is an RF leveling preamp. It uses a mini-circuits mixer as an attenuator. First time I saw one used for that. I had to modify one to smooth the output. It was in the chain between an RF generator and an amplifier putting RF into an anechoic chamber. Before smoothing, at moderately high RF fields the RF was setting off the Halon alarm!

Vince.
--
Michigan VHF Corp. http://www.nobucks.net/ http://www.CDupe.com/
http://www.metalworkingfun.com


Re: MAX9814 integration to uBitX

Guy N7BIR <sgbridge@...>
 

Dave,

just received my Max9814 and was waiting for someone smarter than me to figure out the wiring to the uBITX. I did download the 9814 tutorial from Adafruit but haven’t read it yet. 


Re: AE7EU Top Level PCB Mod

Jerry Gaffke
 

Here's his board design, ADE-1 is bottom-right of the first sheet:
    https://groups.io/g/BITX20/attachment/38900/1/uBitx_top.pdf

Here's the ADE-1 datasheet:  
    https://www.minicircuits.com/pdfs/ADE-1.pdf

ADE-1 pins are as follows:
L=LO       (local oscillator, or vfo)
R=RFIN   (input from antenna, we assume this is a receiver)
I=RFOUT (intermediate frequency)

A current source on the I pin (RFOUT) will flow through the top-left and bottom-right diodes,
With those two diodes conducting, the tops of the two transformers are connected together,
and the bottoms are also.

So the L and R windings are effectively coupled through the two back-to-back transformers.
Signals pass freely from ATT-IN to ATT-OUT when the diodes are conducting.

A neat trick, I've never seen a mixer used as an attenuator.
Though might be cheaper ways than using an ADE-1
And I'm curious how linear this would be for incoming high level RF signals
when partially attenuated.

Jerry, KE7ER


On Fri, Jan 12, 2018 at 09:21 pm, Mike Woods wrote:
Ok - I understand how it works now.  The one remaining question is how injecting DC into the output side (IF pin) of the mixer (as you have it drawn) would unbalance the mixer? Doesn’t this look like a short circuit to the DC? I would have thought you would connect the DC to the LO input to have current flowing through the diodes?
 


Re: AE7EU Top Level PCB Mod

 

Also, why not a whole kit option? would that not cut cost?


Re: AE7EU Top Level PCB Mod

 

I say make a Kickstarter or indigogo. I think more people might be interested in this. I for one would be happy to have all this in one board solving many mods at once. Not to mention an ATU in the bitx just sounds fun!

 

 73

   David


Re: AE7EU Top Level PCB Mod

Diver Martin <diver.martin@...>
 

A reasonable idea. Main thing will be to have both pads close enough together for the 0603, but large enough to accommodate the 1206.  I've done 0603's across a 1206 pad, but it's a PITA, and not easy for fabrication certainly.  I'm sure many fab houses won't like putting an 0603 onto a universal pad though, it'll probably have a greater tendency to tombstone.

On Fri, Jan 12, 2018 at 9:19 PM, Glenn <glennp@...> wrote:
Maybe consider a 'special' footprint that will take any smd size from 0603 to 1206. Seems there is plenty of room, in the main, to do this.

glenn
vk3pe




--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?


Re: AE7EU Top Level PCB Mod

Diver Martin <diver.martin@...>
 

Hi Mike,

Check out the datasheet for the ADE-1 here: https://www.minicircuits.com/pdfs/ADE-1.pdf .  Page 1, bottom right side for the electrical schematic, you'll see the "I" pin has a DC connection to the diodes and then to ground.  This will forward-bias two of the diodes, and reverse-bias the other two.  A current limiting resistor (R14 in this case) limits the current going through the diodes.  I picked 1.2k randomly, it might be 1k-100k, I'll have to play with it I'm sure.

On Fri, Jan 12, 2018 at 9:21 PM, Mike Woods <mhwoods@...> wrote:
Ok - I understand how it works now.  The one remaining question is how injecting DC into the output side (IF pin) of the mixer (as you have it drawn) would unbalance the mixer? Doesn’t this look like a short circuit to the DC? I would have thought you would connect the DC to the LO input to have current flowing through the diodes?

Mike 




--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?


Re: AE7EU Top Level PCB Mod

Mike Woods
 

Ok - I understand how it works now.  The one remaining question is how injecting DC into the output side (IF pin) of the mixer (as you have it drawn) would unbalance the mixer? Doesn’t this look like a short circuit to the DC? I would have thought you would connect the DC to the LO input to have current flowing through the diodes?

Mike 


Re: AE7EU Top Level PCB Mod

Glenn
 

Maybe consider a 'special' footprint that will take any smd size from 0603 to 1206. Seems there is plenty of room, in the main, to do this.

glenn
vk3pe


Re: preorder question #ubitx

August Treubig <atreubig@...>
 

I ordered mine on Dec12 as a preorder.  I just recieved an email that mine has shipped via DHL and to expect it on Tuesday 

Aug
AG5AT


while Im impatiently waiting

K9WIS
 

I ordered a hand full of nano boards to learn more about programming the part and set up my development project..I got it all up and running in a few minutes. I ordered 3 boards for under $10 on ebay and got them in a couple of days.
I also have an SI5351A board from a previuos project..maybe I'll make my own radiouino while Im waiting.

Brian K9WIS


Re: AE7EU Top Level PCB Mod

Diver Martin <diver.martin@...>
 

So, without any major modifications to the pick structure of my design, here's what I got back from Macrofab (US based in TX).

As you can see in the attached, the raw PCB cost is about $95 a pop, in qty 100.  In qty 1000, this goes down to about $75.  This doesn't include any of the Through-hole components though, things like the Teensy32, potentiometers, inductors (in a kit like this, it'd be you-wind), power connectors, and they couldn't quote me the ADE-1 ($2.55).  In total, about $45 in parts not included in that.  This makes the overall PCB $140, not including shipping, or about $150 if you assume about $10 for shipping within the USA, $130 if there were preorders for 1000 (Sorry, I don't have $10k to lose in advance, let alone $100k)

Is it even still reasonable?



On Fri, Jan 12, 2018 at 2:43 PM, Martin Held <diver.martin@...> wrote:
I used a lot of 0603's and such.  Those are a large percent of the assembly cost.  I could go to 1206's pretty easily I think....  A lot of people don't like assembling 0603's.  The other option then might be change a bunch of the resistors to through hole, same for the caps.

A coworker who's used the same assembly house got $0.40 a part for 25 PCB's, at about 180 parts per PCB he said.  That would make the assembly cost about $60.

There are a few places where resistor/capacitor arrays might be applicable in this design, which can significantly reduce costs.

On Fri, Jan 12, 2018 at 2:09 PM, chris gress <Chrisg0wfh@...> wrote:
Could you just get the ic,s fitted make the rest home assembly would that help cut the costs chris

On 12 Jan 2018 21:57, "Diver Martin" <diver.martin@...> wrote:
So, good news, bad news.

Good news: I got a BoM together, defined all the parts, etc.
Bad news:  The BoM (majority single unit pricing from Digikey, but I took out gross single-part costs like 0603 capacitors/resistors/etc) is $112.  This might vary from half to 3/4 depending on the volume, so $60 to $90 or something.  Without knowing the volumes I'd do, it's hard to define.
Good news:  I have a vendor in town that will assemble the boards.
Bad news:  It's about $1 a part to place it on the PCB in a prototype run.  There are 147 SMT parts, assuming the person buying the board installs all TH components, toroids, etc.  That's $150 a PCB for assembly worst case.  In prototype quantities, I was told $1 per part (RoHS $1.20) (qty 1-10 boards).  Past assemblies I've heard down from $0.1 per part to $0.25 per part, so I'm not quite sure where to go on that front, as it's also volume dependant I believe.  I've put out a few pings to those I know who've gotten things built up for a better guestimate, but for now, I'll go with the pessimistic $1/part.

So... Assuming a good case of $75 for the BoM, $10 for the PCB, $15-$150 for assembly, $10 shipping, not including the $500 NRE or my initial builds (so tack on $10 there too assuming a run of 100 PCB's).  Soooo... $110 to $250 is the current price bracket that I've got, the major uncertainty in the cost of per-part placement / assembly.

#1 cost item:  Relays for the tuner and other things ($35)
#2 cost item:  Teensy3.2 ($20)
#3 cost item:  Minicircuits mixer ($3.15)
#4 cost item:  20-turn precision pots ($3 total, eliminate final design)

For those who wish to peruse...  A BoM is attached.


On Wed, Jan 10, 2018 at 10:39 PM, Martin Held <diver.martin@...> wrote:
So, I've finally got a rough draft of what I'm thinking for my uBitx top PCB mod.  Features at this point are:

No modifications required to uBitx board itself (not to say a 470uF anti-pop mod might be bad, or other things couldn't be done)
ATU: 7-inductor, 8-capacitor with Hi-Z/Lo-Z switch.
Selectable Power output (two power input connectors)
Brain transplant:  Teensy3.2 96MHz ARM processor
All connections on side edges - no wiring to enclosure
Front panel with pushbutton switches
DSP Audio (Via Teensy32, would require headphones or amplified speakers)
Solderless AGC modification (Attenuator at the front end switched in during RX)
Realtime clock (via Teensy32)
Linear amplifier control (just a reed relay on a 3.5mm header, sorry, not an RCA, but you could easily change it...)
Top side only construction (would make assembly cost lower)

BoM cost:  Probably way higher than it should be.  Needs optimization, and I still need to enter in costs.
Complexity:  Probably way more than it should be.
Layout:  An ugly mess of routing.  I can't say I like it, but the constraints I put on myself made it really hard to route.  There's lots of open areas to cross with lots of signals going all different directions.

Picture of the layout and schematic PDF attached, along with a 3D view.

I think the one modification that I still need to consider is a microphone preamp.  But, I have no flippin' clue where on the PCB I'd put the gain control knob!  Might have to be an internal potentiometer....

--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?



--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?




--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?



--
Martin Held - AE7EU
http://ae7eu.com/
-------------------------------------------------------------------------------
If there aren't any questions, then what is there to learn?