Date   

Re: Homebrew from scratch #ubitx

Clark Martin
 

The best thing about standards is everyone implements them differently.


Clark Martin
KK6ISP

On Jun 21, 2018, at 5:57 PM, VK3HN <prt459@...> wrote:

Yes, absolutely, let's all propose an IEEE Standards Committee for HamBus, with meetings at exotic locations for the next 5 years..  And yes, the best thing about standards is there are so many to choose from.

experience with Sunil VU3SUA's enclosures #ubitx

Mike KK7ER
 

My young son got an Elenco FM radio kit for Christmas.  We built it together and now he is hooked.  He is studying for his technician license.
He has a birthday coming up so a few weeks back, I ordered a uBitX and one of Sunil Lakhani's cases.
The uBitX came in about a week.  Despite my credit card being charged immediately, I never received any acknowledgment of the case order.  I have tried to contact Sunil through several different channels but have gotten no response.  There were 12 of the cases in stock at the time of the order.  I am wondering if I should dispute the credit card charge or keep waiting.  What has been the experience of people in this group who have ordered cases from Sunil?  Has he come through?  What was time from order to delivery (in the US)?  Did you have trouble with communication about your order?

Thanks and 73,
Mike KK7ER

Re: Thoughts on a Ham Bus

VK3HN
 

My problem with the bus concept is that some but not all connections between analog modules are amenable to bussing.  

Control or signal lines that are needed by more than one module -- such as clocks, power, ground, control lines (+tx, +rx, band select, USB/LSB select, IF filter select, PTT, key, T/R relay) -- fit the bus model well.  Modules using these lines would not be location-dependent on the bus -- they could be plugged in in any sequence.  

The signal paths in a typical transmitter/receiver, however, are point to point and form a serial chain of modules -- eg. antenna T/R relay (and optionally LPF) -> BPF ->  RF amp -> Rx mixer -> xtal filter -> Product detector -> Audio preamp -> Audio filter -> Audio power amp.  I can't see an obvious answer to how to make these serial point to point connections on a bus.  

If I were to prototype this, I'd most likely run these signal paths in coax along the sides of the modules, not using the bus but floating the coax lines above the bus, between modules, perhaps with SMA or some connector type.  This compromises the bus model a bit (not all connections come in or go out of the edge connector/header, two module connection/disconnection points) but to put these connections on the bus complicates the bus and couples small signals and sensitive amplifier inputs to long parallel bus lines.

So the best I can imagine is a pseudo 'Hambus'. with control lines on the bus and signal interconnections not on the bus  

73 Paul VK3HN.    

Re: ND6T AGC and Click kit wiring notes

Glenn
 

Kees,
I think there is an error on the AGC pcb overlay. The hole marked as "5v" is actually ground. The hole adjacent is 5v.

glenn vk3pe


On Thu, Jun 21, 2018 at 05:14 pm, Kees T wrote:
I have updated the AGC/Click mini-kit "ordered/shipped" list in the "Files" section per today's information. There will be some delay before more kits can be shipped because I'm out of AGC boards and have just ordered another 160. I have plenty of parts.

73 Kees K5BCQ

Re: Thoughts on a Ham Bus

Rahul Srivastava
 

While formulating for a suitable HAM bus with current technology we have to consider many aspects. Most modern design will use mix of analog and digital technology, requirements become more critical when we throw in DSP and other features. Atlas bus in HPSDR was designed  with mainly digital signals running thru backplane. Such high speed signals between multiple FPGA's resulted in lot of cross talk. For BITX series with all the new enhancements ground separation becomes a critical issue. 

I feel for a simple design like uBitx , Elecrafts K2 approach suits us better with one main board with PA and other circuitry and provision for swap able plug in modules.  Si , mixers , PA, BPF  and LPF can be on main board. TIA and multiple stacked xtal filter modules can be swap able. Front panel can house the digital section ie Nano, LCD and controls. All boards to be plug in type.

73 

Rahul VU3WJM

Re: KD8CEC Firmware

Ashhar Farhan
 

The settings are carried over


On Fri, 22 Jun 2018, 08:40 Terence Taylor, <n6mon@...> wrote:
I am probably shortly going to be installing the KD8CEC firmware on my µBitx.
I do have one question, will the Raduino retain the alignment settings, or will I have to redo all of the alignment steps?




KD8CEC Firmware

Terence Taylor
 

I am probably shortly going to be installing the KD8CEC firmware on my µBitx.
I do have one question, will the Raduino retain the alignment settings, or will I have to redo all of the alignment steps?

Re: Understanding Spurious Emissions

Howard Fidel
 

Got it. Thanks. I never saw on my uBitx the numbers you reported, but I don't think it is a serious problem for a barefoot uBitx, which is the main point I was trying to make. It seemed like the group was spending a lot of energy on something that is like driving 60 MPH in a 55 zone.

On 6/21/2018 7:22 PM, ajparent1/KB1GMX wrote:
Howard,

The mixer where the spur is generated is the mixer formed by T2/T3 that is about 
28db (after allowing for filter losses and all)  later in the stream and if that mixer
is overloaded you get the spur.  The driving modulator is then underdriven.

Work it backward.  If that mixer is overloaded at -7 oir -10DBM what got to be
happening well before that?   And that mixer can easily be driven to its 1DB
compression or worse without hurting the audio to the ear.

Allison

Re: RF Situation Resolved.

Howard Fidel
 

Glad to help.

On 6/21/2018 4:03 PM, Latham, Chip wrote:
Howard (WB2VXW) called this morning and we went thru quite a bit of testing and things were not added up, until I mentioned that I had replaced the heatsink, made sure it was isolated from ground but forgot the FETs needed to be isolated from each other as well.
Thanks Howard, that was a stupid mistake on my part. I own it!
Farhan forgive me for suggesting there might have been a possibility of rushing the board out, getting ready for the release of V4.0
Chip
N5FJK

Re: Encoder problem

Howard Fidel
 

So there are several possibilities. I had the same problem initially, when I realized that I didn't wire it correctly. I fixed the wiring and it worked. It could be a bad encoder, incorrect wiring or a bad Raduino, or corrupted software. If you have a two channel scope you can look at the two outputs signals, they should create 2 pulse trains shifted be 90 degrees when you turn the knob. The phase shift reverses when you change direction. Most likely if both have pulses they are phased correctly, but if one or both don't, it wont work. If you see the pulses, it is not the encoder.

Howard

On 6/21/2018 4:32 PM, n7nsd@... wrote:
And yes, rotating only causes the display to flicker the last two freq digit from zero to fifty. After pressing the encoder and getting the change band option, turning causes no change. Same with the next press and then back to 40m where it won’t change freq. 

Re: Thoughts on a Ham Bus

Tim Gorman
 

I think you have hit on the only standard that would work for amateur
equipment.

I have used this type of construction for several pieces of equipment.
The pcb's can be shielded using cheap copper flashing from Hobby Lobby
using either feedthrough capacitors or rg-174 with the coax shield
soldered to the flashing where it goes through it.

A 100mmx100mm is about 4"x4". That's large enough for almost any stage,
be it rf, if, or audio. If we could standardize on interconnect design
between modules I'm not sure anything better would be needed.

tim ab0wr

On Thu, 21 Jun 2018 17:12:32 -0700
"Glenn" <glennp@...> wrote:
my thoughts, as indicated in these posts  its very hard to come up
with a 'universal' BUS.

I think a BUS suited to the project in  hand like uBITX, or one with
a similar 'block diagram' is a better idea.

And, I believe, it needs to take into account, the price of PCB's.
The 100x100mm size is the magic size for good deals out of China and
perhaps the bus should consider this as a standard size PCB. OK, it
will probably mean more 'blocks' are on each of these larger pcb's,
but even so, still leave some room for change.

glenn vk3pe


Re: Audio feedback during transmit? #ubitx

Mark M
 

Mine started doing it when I installed the ND6T/K5BCQ AGC board. It's not a ground issue, when I remove the board it stops. It looks to be correctly wired but I suppose I coulda fried something...it was my first real SMD assembly effort. It happens even with the board not connected to the RF path, i.e. just 5v and VOL-H connected. I suspect I screwed it up somehow. Maybe I'll assemble the second one I have and see if it works any differently.

Mark     AA7TA

Re: Homebrew from scratch #ubitx

VK3HN
 

Yes, absolutely, let's all propose an IEEE Standards Committee for HamBus, with meetings at exotic locations for the next 5 years..  And yes, the best thing about standards is there are so many to choose from.

My problem with the Hambus concept is that some but not all connections between analog modules are amenable to bussing.  

Control or signal lines that are needed by more than one module -- such as clocks, power, ground, control lines (+tx, +rx, band select, USB/LSB select, IF filter select, PTT, key, T/R relay) -- fit the bus model well.  Modules using these lines would not be location-dependent on the bus -- they could be plugged in in any sequence.  

The signal paths in a typical transmitter/receiver, however, are point to point and form a serial chain of modules -- eg. antenna T/R relay (and optionally LPF) -> BPF ->  RF amp -> Rx mixer -> xtal filter -> Product detector -> Audio preamp -> Audio filter -> Audio power amp.  I can't see an obvious answer to how to make these serial point to point connections on a bus. 

If I were to prototype this, I'd most likely run these signal paths in coax along the sides of the modules, not using the bus but floating the coax lines above the bus, between modules, perhaps with SMA or some connector type.  This compromises the bus model a bit (not all connections come in or go out of the edge connector/header, two module connection/disconnection points) but to put these connections on the bus complicates the bus and couples small signals and sensitive amplifier inputs to long parallel bus lines.

So the best I can imagine is a pseudo 'Hambus'. with control lines on the bus and signal interconnections not on the bus   Any comments?

73 Paul VK3HN.    

  

Re: uBitX CW Sidetone Volume

Skip Davis
 

I put one end of the pot and wiper where R250 was that worked for me, now mine doesn’t blast my ears off with headphones. 

Skip Davis, NC9O 

On Jun 21, 2018, at 18:18, Mark M <junquemaile@...> wrote:

Thanks, Skip, I was thinking along those lines. Did you put the pot between CW-TONE and ground and feed the wiper onward or put one end of the pot & the wiper where R250 was?

Mark    AA7TA

Re: Nextion Display vs 1602 LCD - Current Consumption #ubitx

Lowell Haney
 

I posted this in the wrong topic so I've moved it here.

Just got in a 2.4 and a 3.2 Nextion display.  I'd seen some comments on the current draw and the possible need for a heat sink on the existing 5V regulator or maybe even a separate supply. So I just measured both on the bench.

Supply voltage was 5.04 VDC.
2.4 display was 125 ma.  3.2 display was 110 ma.  Both at full brightness.

These are both above (~25 to 35 or so) what is listed on the manufacturers website.

I did not check with the display in sleep mode.

Re: Microscope - - new thread

Gwen Patton
 

The $60 Chinese microscope is actually kind of nice. It's a whole lot better than the $15 Chinese USB microscope I've been trying to work with -- about 10X as stable, easier to focus, an actual stage to place a board on under the camera, and it's RECHARGEABLE. The USB microscope had me twisting my neck to look in the bench PC's monitor while trying to work on the board in its view, which is insanely uncomfortable as well as disorienting, and just when I'd start making decent solder connections with the silly thing, the suction cup base would give way and the camera would fall on its face, right into my work, which would then bounce any loose parts all over the bench and the floor.

This thing, while certainly no AmScope, at least has me looking straight ahead, only a few inches above the work instead of at a 40 degree angle to the left and eight inches up. It doesn't tie up my bench PC because it's self-contained. It doesn't send pictures to my computer, but I can pop out the microSD and read THOSE on the computer if I really need to. The picture is sharper with this thing than the USB microscope, and it doesn't take up a lot of bench real estate.

Do I still want a nice AmScope stereoscopic microscope? Sure I do. But the next big purchase for the bench is going to probably be a 3d printer...and after that, it'll likely be Christmas, and I think I'm going to logroll to get one of those RFinder DMR Android thingers. The M1 in particular looks nifty...but I'm easily amused by shiny objects and fancy electronic gadgets. And musical instruments, of course. I meant to practice the violin today, but got sucked into my uBitX build, disassembling my initial wiring and installing the breakout boards for the 3.5mm jacks and the encoder that I got from W0EB. (Those worked great, Jim, except that there was insufficient clearance for one of the sockets to be installed level with the main board because the 3d printed back plate had two of the holes too close together. I made it work, though.) But I digress...

The $60 self-contained Chinese electronic microscope actually works quite well, and should give me a good enough view to start practicing with SMD building. I unpacked my i-Extruder and set it up with a syringe of Amtech NC-559-V2-TF Tacky Flux I got from Louis Rossmann in NYC. I figure it'll be a while before I'm ready to start using the i-Extruder for solder paste, but I can make use of it for flux right away. (Great gadget, that. I backed it on Kickstarter. https://www.i-extruder.com/en/) Eventually, I'll probably get the pick-n-place pen accessory, the foot pedal, and the stand for it.

Gwen, NG3P

Re: ND6T AGC and Click kit wiring notes

Kees T
 

I have updated the AGC/Click mini-kit "ordered/shipped" list in the "Files" section per today's information. There will be some delay before more kits can be shipped because I'm out of AGC boards and have just ordered another 160. I have plenty of parts.

73 Kees K5BCQ

Re: Thoughts on a Ham Bus

Glenn
 

my thoughts, as indicated in these posts  its very hard to come up with a 'universal' BUS.

I think a BUS suited to the project in  hand like uBITX, or one with a similar 'block diagram' is a better idea.

And, I believe, it needs to take into account, the price of PCB's. The 100x100mm size is the magic size for good deals out of China and perhaps the bus should consider this as a standard size PCB. OK, it will probably mean more 'blocks' are on each of these larger pcb's, but even so, still leave some room for change.

glenn vk3pe

Re: TDA 28222

Daniel Conklin
 

Mine has the WX brand TDA2822.  I put a 6v regulator in the 12v supply line to the chip as suggested on this group and it has been working fine for a couple of months now.  The audio is loud and clear.  
Daniel, W2DLC

Re: Encoder problem

ajparent1/KB1GMX
 

I've used these encoders for other things and yes they are fragile.

I got so annoyed with the one on the Raduino I pulled and ancient mechanical
mouse out of junk, the kind with a DB9 serial connection and a rolling ball in
the bottom.  Pulled out the slotted wheel and the emitter/detector pair and
using the remains of a old Clarostat pot for the shaft and the bearing made
an optical encoder.  Its much more rugged, works well, and has better feel,
smoother.

Allison