Date   
Re: SMD Group Build

William R Maxwell
 

They have, Jack. Well, sort of but you would have to adopt my favourite 0805 size. See eBay item

131871397971

A good assortment and at a good price. So good that any mark up in the price must be very small. In fact at that price, each of your club members should be encouraged to buy in a pack each. That way they would have enough for your smd introductory project board and then heaps left over for future projects.

Bill, VK7MX


On 25/01/2018 4:23 PM, Jack Purdu
m via Groups.Io wrote:
I wish someone would put together an assortment of, say, 40 common values, quantity 100 of each value and market it for some reasonable markup for resistors and caps. For the club build, I'd prefer 1206 since this is a huge step for some of the club members.

BTW, today I just got 40 clear plastic 1.25"x0.75" cosmetic sample jars (eBay #332506418787). Tomorrow I'm going to Target and buy Velcro sticky tape "dots" and place one half on the bottom of the jar, and the other on a piece of plywood which hangs on the wall. Now if somebody has an assortment of 40 common values, they go into the jar and I'm ready to go. Each jar will have a small Avery label on it.

Jack, W8TEE



From: Diver Martin <diver.martin@...>
To: BITX20@groups.io
Sent: Thursday, January 25, 2018 12:09 AM
Subject: Re: [BITX20] SMD Group Build

Jack,

Just as a point of reference:  Going for 5% tolerance 1k ohm resistors, and buying 1000 at a time, a quick search on digikey gives me:

1000x 0603 resistors:  $2.07
1000x 0805 resistors:  $3.03
1000x 1206 resistors:  $4.63

For reference
1000x axial TH resistors: $7.29.

At a half penny a pop, the cost of 1206 vs 0603 I'm betting isn't going to be a noticable difference.  (At 100qty, they're about 2x as much, ~$0.01 each, or $1 for 100).  You can really sneeze hard and not loose a lot of money.



On Wed, Jan 24, 2018 at 8:20 PM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:
I can barely see a 0603! I would prefer 1206 if I can find them and am not too worried about the cost differential.
Jack, W8TEE


From: Clark Martin <kk6isp@...>
To: BITX20@groups.io
Sent: Wednesday, January 24, 2018 9:15 PM
Subject: Re: [BITX20] SMD Group Build


Clark Martin
KK6ISP

On Jan 24, 2018, at 5:56 PM, Diver Martin <diver.martin@...> wrote:

Mouser & Digikey are my go-to for SMT parts.  They carry just about everything.  If you have other oddball SMT stuff, and either one are out, head to findchips.com.  There are alternate suppliers, but those two always have what I need, either in the exact specified part number, or an equivalent.  Other places will source 1206's and stuff, but might only sell by the full reel (which I have yet to need, except maybe 0.01uF caps or 0.1uF caps across multiple, multiple projects).

SMD resistors/caps (0603, 5% in my case) are usually cheap enough that I buy them in 1000-piece quantity, because $2 of parts for life or $0.5 for the parts I need for the project, and to always have them on hand, is easy.


I’ve only bought from Digikey a few times but I use Mouser all the time.  Also there are Newark and Allied for such supplies.

I bought a set of 0805 resistors (from 0 ohm through several Mohms) and a set of 0805 caps (10s of pF through 1µF).  They came on cards that fit a day planner binder.  There are between 1 and four strips of 25 each for each value (depending on expected usage levels).  I have little trouble working with 0805 parts and they  fit nicely on .1” grid perfboard (with plated through holes).  

When I use up a strip I buy a new strip of 25 at a local electronics shop (Silicon Valley still has a few).

I haven’t done any PCB fabricating yet but that is in the plans.

SMD diodes and transistors of most any size are easily soldered to perfboard.

I’ve also soldered up to 8 pin SOICss buy putting alternate pins on the perfboard pads and tack soldering leads to the other pins.

It definitely makes for smaller boards.





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



Re: Software support Request for Full QSK BITX40

Gary O'Neil
 

Oh my...

Pretty much the responses I’ve anticipated... 

Nothing should be considered ready for prime time... 1uF caps are big... They exacerbate problems you want (might want) to investigate in simulation. Perform a transient analysis of the mic amp as an example, and you will get a clear (visual) picture of the T/R transition noise far beyond when the relays stop their chatter. Making the capacitors too small is another way to stress circuit performance. 

The 2N7002 is included in the LTSpice library... I have a healthy stash of 2N7000’s... close enough for feasibility testing.  May or may not be the device of choice. That said, preliminary testing at 20W CW survived a 5:1 mismatch, and output to the receiver was insufficient to bias the protection diodes... of which only one would fully protect the front end... Can you guess why? I think the configuration shown is close to the prototype I tested... I don’t have my most recent configuration/data yet documented, but my prototype measurements were something like 0.2 dB insertion loss and 45 dB isolation (simulated) >50 dB (measured). Actual isolation improves as the match improves... i.e. >50 dB was measured when the match was 1:1.

The transmitter impedance can be 50 ohms or infinity, but as configured is likely closer to 50 ohms. In either case, the antenna is tuned to the system (combined) impedance. MDS sensitivity remains below 0.1 uV, and Transmit output power is unaltered. 

This is not a radio redesign, but rather a make best of what I’ve been given. A redesign is on my radar however, that eliminates three of the 6 IF amp stages, the two on board oscillators, and at least one audio stage. A board relayout, some novel switching, 
Some filter improvements, and possibly trying to integrate Wes’s bidirectional amp scheme into the design. 

I could answer to all of the obvious and not so obvious questions and go off in other directions, but my intent is to make the as is design work with Allard’s feature rich software in its most favorable manner. I think it could result in a really decent radio at its price point... Assuming builders don’t have to achieve it on a second or third pass. 

Ill post where here this ends up, but once Allard has his code supporting Full QSK, I’ll likely go radio silent again until I reach another hurdle, or I actually achieve the result I’m after that’s sufficiently robust that I can suggest it to others without reservation.

72

Gary, N3GO

BITX 40 for sale

Bruce Bjerke, K7BHB <bruce.k7bhb@...>
 

Selling my BITX40 to raise sheckles for another rig. The unit operates perfectly, and gets good reports from the Noon-Time Net here in the Pacific Northwest. Equipped with the Baofeng speaker-mic, receive audio currently wired to a 2" speaker. Attractively cased in a clear plastic box with easy access to the internals. I'm running Allard's V1.26 with the frequency range set to 7.125 - 7.300 KHz., and shuttle tuning rate set well down. I've installed a fine tuning control and function button.
Includes a spare unused 2-line LCD module. The rig is suitable for an appliance operator or for someone wanting to pursue further modification and programming. Photos upon request. Selling for $99.00 shipped USPS Priority Mail. Contact me through the Board, or at bruce dot k7bhb at gmail dot com.

Re: SMD Group Build

Clark Martin
 

IIRC this is the place where I bought SMD parts some time ago.  They still have the day planner hole pattern.  I find that very convenient.  I put the resistors and caps in one binder and whenever I need one I just go leafing through it.

0805 SMD Resistor Kit 80 Value Total 2000 Pieces Surface mount - MDFLY






Clark Martin
KK6ISP

On Jan 24, 2018, at 9:23 PM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:

I wish someone would put together an assortment of, say, 40 common values, quantity 100 of each value and market it for some reasonable markup for resistors and caps. For the club build, I'd prefer 1206 since this is a huge step for some of the club members. 

BTW, today I just got 40 clear plastic 1.25"x0.75" cosmetic sample jars (eBay #332506418787). Tomorrow I'm going to Target and buy Velcro sticky tape "dots" and place one half on the bottom of the jar, and the other on a piece of plywood which hangs on the wall. Now if somebody has an assortment of 40 common values, they go into the jar and I'm ready to go. Each jar will have a small Avery label on it.



Re: uBitx TX performance with frequency

Alex - PA1FOX
 

Bob,

Yes, I've seen similar behaviour on my homebrew uBitx. Increasing the drive will overload the PA at 80 meters but will hardly increase the power output at the high bands. I even made a change in the driver circuit that decreases the gain below 10MHZ so I could crank up the overall gain of the TX chain more trying to get more output at 14MHz and up. No success. After extensive experiments I've decided to replace the IRF510's with RD16HHF1 mosfets (not pin-compatible!).

I am now optimizing the output transformer and impedance levels but so far the TX power ranges from 10 watts at 80m to 8 watts at 17m. The 15m and up LPF is not finished yet, but reviewing the specs of the RF16HHF1 I don't expect much further power drop at 28 MHz.

Secondly I like the idea of the housing of these mosfets being the source, so a direct grounding to the case is easy. No insulation material needed and a better RF ground.

A slight disadvantage is that the bias current of the RD16HHF1 is a little higher, but that's ok for me.
If you should make such a change with the commercial PCB version, beware of the pin incompatibility.

73, Alex
PA1FOX

Re: uBitx TX performance with frequency

chris gress <Chrisg0wfh@...>
 

Alex when you have your modifications all done can you please post it on here I am interested in doing mine when I get it chris

On 25 Jan 2018 07:37, "Alex Buurlage" <pa1fox@...> wrote:
Bob,

Yes, I've seen similar behaviour on my homebrew uBitx. Increasing the drive will overload the PA at 80 meters but will hardly increase the power output at the high bands. I even made a change in the driver circuit that decreases the gain below 10MHZ so I could crank up the overall gain of the TX chain more trying to get more output at 14MHz and up. No success. After extensive experiments I've decided to replace the IRF510's with RD16HHF1 mosfets (not pin-compatible!).

I am now optimizing the output transformer and impedance levels but so far the TX power ranges from 10 watts at 80m to 8 watts at 17m. The 15m and up LPF is not finished yet, but reviewing the specs of the RF16HHF1 I don't expect much further power drop at 28 MHz.

Secondly I like the idea of the housing of these mosfets being the source, so a direct grounding to the case is easy. No insulation material needed and a better RF ground.

A slight disadvantage is that the bias current of the RD16HHF1 is a little higher, but that's ok for me.
If you should make such a change with the commercial PCB version, beware of the pin incompatibility.

73, Alex
PA1FOX


Re: uBitx TX performance with frequency

Lawrence Galea
 

Farhan
I know it will increase the price, but how about switching over to the RD16HVF1 which would allow the rig to run from 12V doing away with those wanting more power to increase the voltage to the PA?
Would also do away with the PA heatsinks if the case is metal and it is used as the heatsink.
Regards
Lawrence

On Thu, Jan 25, 2018 at 6:23 AM, Ashhar Farhan <farhanbox@...> wrote:
You can increase drive with the preset of the predriver.
- f

On 24 Jan 2018 6:24 pm, "KD8CGH" <rkayakr@...> wrote:
I took some time to measure the actual performance of my uBitx with its original calibration against a dummy load. The instruments used are not lab calibrated. I did check my wattmeter against my recently factory calibrated K3 and found the power reported to be about 5% high. The power supply is rated as 25 amps and set at 13.7 volts. I tested by simply pressing the PTT (no audio input, power out 0) and keying CW.
Receive current: .25 A

  PTT CW CW
f kHz I amp I amp P watt
3,530 0.74 1.8 8
3,970 0.74 2.1 9
7,030 0.73 1.57 5
7,270 0.7 1.6 5
10,113 0.72 1.22 3
14,030 0.71 1.34 3
14,320 0.71 1.37 3
21,170 0.69 0.96 1
28,900 0.69 0.83 0.5

The results agreed in general with Dave's (WI6R) post https://groups.io/g/BITX20/message/39578, although his results start a bit higher and end even lower.
Although my current draw with PTT down agrees with the value specified on the Tune-up page, I never quite see 10 watts out. The 80 meter power isn't too bad, but the 14 MHz is half and 28 MHz is 1/4 of that mentioned on the uBitx web page.

What TX performance have others seen?
Any fixes for higher frequencies?

     Bob   KD8CGH


Re: Second batch of uBITX shipping? #ubitx

Cor Beijersbergen
 

I ordered mine december 12th. I received it as 009/2 in France on january 19th.

Cor - PA4

Re: Second batch of uBITX shipping? #ubitx

Nigel G4ZAL
 

Yes, as per my first (top) post - late on 13th Dec 2017

Nigel

Re: ubitx and I2C LCD noise

Dimitar Pavlov
 

Hi,

This is normal, when both of them have has used the same arduino pins: A4 and A5. Need short cables, and also You might to use SPI interface for display and I2C for Si5351.
(It's easy to convert arduino sketch with other library)

73!LZ1DPN

Re: Creating Gerber files for pcb construction

Gordon Gibby <ggibby@...>
 

William Maxwell—Aha!!  Thanks, now I understand.   73, 


Sent from my iPhone

On Jan 24, 2018, at 23:41, William R Maxwell <wrmaxwell@...> wrote:

If you play around with the quantity on the on-line quotation screen on the website of just about any othe Chinese manufacturers, you will see that 10 boards usually cost exactly the same total as any lesser quantity, provided the size is within the specified maximum for their current special offer, usually a maximum of 100mm x 100mm. Hence my hint of a week or so back to order 10.

Bill VK7MX

On 25/01/2018 10:57 AM, Gordon Gibby wrote:
First set of boards arrived today -- not sure why they shipped me TEN boards, I only ordered five.
This is all new to me.   Soldered in header sockets.   Wished I'da thought of that for ALL the i/o connections.

Found at least one error so far -- forgot to ground pin 5 of the LCD display.   Have not soldered in the op amp portion but got the LCD working (after adding little ground wire) and verified that the Adafruit Si5351 is bring controlled --- communications receiver hears  it right where I send its frequency to.   

This so SO cool.....   

Can't believe how much this forum has taught me in just a few weeks.
This is going to be huge for our local ARES group.   Loads of skills they can learn.

Gordon

________________________________________
From: BITX20@groups.io <BITX20@groups.io> on behalf of Gordon Gibby <ggibby@...>
Sent: Tuesday, January 23, 2018 4:35 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Creating Gerber files for pcb construction

I don't have the exact number, but one company was about $24 (including shipping) and the other company was $28 (including shipping) --- 5 boards each company.   First time customer.

________________________________________
From: BITX20@groups.io <BITX20@groups.io> on behalf of B C <k9wis@...>
Sent: Tuesday, January 23, 2018 4:19 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Creating Gerber files for pcb construction

what did those boards cost you??
Brian K9WIS

---- Gordon Gibby <ggibby@...> wrote:
​Thanks to all your suggestions I made two trial orders:

pcbway.com

jlcpcb.com


About last friday night/saturday.

The first set is supposed to arrive sometime tomorrow (wednesday)

and the other set on Thursday.   amazing.


Fingers crossed that I did this correctly!!!


Showed this project to my youngest son (working as a new auto mechanic) and he was motivated to get out the christmas arduino kit I gave him and immediately started building LED circuits....astonishing my wife and me....may help him out in life.




________________________________
From: BITX20@groups.io <BITX20@groups.io> on behalf of Gordon Gibby <ggibby@...>
Sent: Sunday, January 21, 2018 12:09 AM
To: BITX20@groups.io
Subject: Re: [BITX20] Creating Gerber files for pcb construction


Thanks for yet another great suggestion.


I have now created a "flying jumpers" breadboard version using a couple of different resistive bridge designs --- the K6BEZ design driven by the Si5351 directly  didn't produce enough voltage to make the reverse measurement accurate and I gave up after several hours on that.   Would need to add an amplification stage I believe...   The easy swr indicator kit from https://urldefense.proofpoint.com/v2/url?u=http-3A__www.qrpkits.com_ezseries.html-23ezswr&d=DwIFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=E2shNumHkU2z89FEz9fB1rmv1B9-9CwkXYgBQ56sX18&s=wATr3kl2cd5RzPMIGfxbDzykiABvusgbH-fnLXPAkSA&e=<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.qrpkits.com_ezseries.html-23ezswr&d=DwMFAw&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=McWMTsaWY88BIHjI9RhDX8BXq0BroHl6MaH6P7zGTVo&s=iOg3ff6bkbrqV9BQbMsupWJHkEUhFqFcHTVOepLM0YM&e=>  (no LED, just take the rectified voltage and run into an op amp with a gain of about 6)  produced a voltage that seemed to work.   My circuit is sorta haywire (with egloo jumpers everywhere) and the pcb version would be FAR MORE STABLE but I'm able to measure  shorts, 25 ohm, 50 ohm, 100 ohm, 220 ohm and open circuit and get  "sorta close SWR" measurements at frequencies up to maybe 30 MHz.   There is so much haywiredness to the breadboard that I can't make any better observations at the moment.   The PCB should be a ton more mechanically stable.  Earlier today I put it on a real antenna and it did find the resonance.


A friend is working on the "single meter" SWR version using a toroidial swr measurement head (which I also have built and should also work).   The goal there is to emulate the $129 LDG big meter display of SWR.....    The pcb that I cranked out (and now being built in China, fingers crossed!) should work with both.   (2 different inputs).


You folks are a lot brighter at this stuff than I am but it has been a ton of fun just getting this much to work!  I think this is going to be a great building project for our ARES group.






________________________________
From: BITX20@groups.io <BITX20@groups.io> on behalf of William R Maxwell <wrmaxwell@...>
Sent: Saturday, January 20, 2018 5:02 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Creating Gerber files for pcb construction


Another to consider is www.jlcpcb.com<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.jlcpcb.com&d=DwMF-g&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=IdE0tYxjCfc0L_NPXEC5rll-igwhgt6ppqTzraUYlNc&s=WtrSAHHYrh1yu_YDRixyHaUjQzv0a3Hp9-zY2b8fanM&e=>. I have just received 10 boards for a mere $2 total, including DHL shipping.  Note the there is a sixe limit of 100mmx100mm, and two layers, green solder resist and 1.6mm material.

This offer I think is limited to your initial order. A subsequent set of 3 boards, 10 copies each, cost me $29, including shipping.

Bill, VK7MX

On 21/01/2018 12:38 AM, Gordon Gibby wrote:
Wow!!! Thank you for that wonderful tip.

Sent from my iPhone

On Jan 20, 2018, at 06:51, Kerr Smith <kerrsmithusa@...<mailto:kerrsmithusa@...>> wrote:

Have you looked at PCB Shopper? You just set the size of your PCB and how any boards you require and it will list all the main PCB fabrication sites and how much it will cost:

https://urldefense.proofpoint.com/v2/url?u=https-3A__pcbshopper.com&d=DwIFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=E2shNumHkU2z89FEz9fB1rmv1B9-9CwkXYgBQ56sX18&s=0xNqpq13ii9aT1Sh5iz_prDuqOsArD7fo-GvxVduS2A&e=<https://urldefense.proofpoint.com/v2/url?u=https-3A__pcbshopper.com&d=DwMFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=tVwyxBAPRZNQpdExa-g1tsq8okRaE7YCQUjWUUW6hMg&s=x1CZZZOSFNIXEjRrVRTlehkNhcaChUif1k7nsMKwx4Q&e=>

For my latest PCBs I tried AllPCB and was extremely pleased with the results, they had an offer on at the time so for $5 I got 7 boards on one order and for my second $5 order I got 17 boards (if your boards are small they seem to add in extra to your order) - they were all shipped using TNT and arrived in just 5 days. At the current time the total cost is $12 for 5 boards up to 35mm x 35mm with free TNT shipping:

https://urldefense.proofpoint.com/v2/url?u=http-3A__www.allpcb.com&d=DwIFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=E2shNumHkU2z89FEz9fB1rmv1B9-9CwkXYgBQ56sX18&s=XnTdlYHqFlKmjNeCLrFl6eNp9UdCG5Xzx2kDDYXCyOg&e=<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.allpcb.com_setinvite.aspx-3Finviteid-3D30276-26url-3Dhttp-3A__www.allpcb.com_online-5Fquote.html&d=DwMFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=tVwyxBAPRZNQpdExa-g1tsq8okRaE7YCQUjWUUW6hMg&s=VRALDmdsziyoxueeKz6mXPEvcc6DHC3hcVq_mlvqGIo&e=>

The other site I would recommend is OSHPark:

https://urldefense.proofpoint.com/v2/url?u=https-3A__oshpark.com&d=DwIFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=E2shNumHkU2z89FEz9fB1rmv1B9-9CwkXYgBQ56sX18&s=z3OHoUEftZQXgilq__PmOkVk9mUQmTqOuH12jAGHT0c&e=<https://urldefense.proofpoint.com/v2/url?u=https-3A__oshpark.com_&d=DwMFaQ&c=pZJPUDQ3SB9JplYbifm4nt2lEVG5pWx2KikqINpWlZM&r=3ELgZgmTnPzGsfvQxkd1S_2NGLYM8sHTxVCQKFxhVXQ&m=tVwyxBAPRZNQpdExa-g1tsq8okRaE7YCQUjWUUW6hMg&s=dqHZt9-lgSwySoNuMqvHedfU_5GT-Uu8usvQgbFEknc&e=>

They are the ones who do the purple PCBs which look really great and also pretty cheap, only a few dollars (around $9.50) for three 35mm x 35mm boards with shipping included.

I am so pleased that the price for creating PCBs yourself is now this low, up until now I have been carefully making my own by etching them but now I can get them in a few days if I need them fast or a couple of weeks if I don't mind waiting. There are so many different fabrication sites there is always going to be a great deal to be had if you shop around a bit, the PCB Shopper site I mentioned above is really great for this.












Re: BITX40 V2.3 update

DaveC <murzim@...>
 

Allard
Thanks
73 Dave G8PGO

Re: SMD Group Build

Ken KM4NFQ <km4nfq@...>
 

Hello Jack, W8TEE,

The SMD components are not the only thing that you might need.
Also look into:
Solder paste in a syringe with application needles (~ $20+ for 35gm)
Toaster Oven or Electric Skillet for melting the solder onto the PCB (find in a thrift store)
Tweezers (for manually placing the components)
Hot Air Gun (for removing parts)
Magnifying Loupe (for inspecting your work)
Desoldering wick (removing solder bridges from ICs)
Soldering Iron with fine tip (rework tombstoned parts)

The revolving LED kit is a challenge to build for beginners.
$3 - $4 per person in the group. All the components are in the kit.
The circuit itself is in the middle of the PCB.
But there are three columns of practice components on each side.
1206, 0805, 0805, 0603, 0603, and 0402 sizes are included, so you get an idea.
The practice columns are not connected to the revolving LED circuit.
The revolving LED circuit has a 555 and a CMOS 4017, as well as
transistors, diodes, and LEDs, so you get a variety of SMDs to work with.

In my recent and limited experience, making an SMD project consists of:
Identifying the components.
Applying solder paste evenly to the pads.
Placing the SMD components on the solder paste.
All the components are soldered at once.
Clean the flux from around the components (Isopropyl Alcohol & toothbrush)
Smoke test.
Only part of my circuit worked, but I got some SMD soldering practice for $3 - $4.

Regards,
Ken, KM4NFQ






On Wed, Jan 24, 2018 at 8:27 PM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:
All:

We have a small group of local hams who enjoy building stuff, yet most are scared to death of SMD parts. Our last build had 29 do the build which is about half of our group. What I'd like to do is put together a small SMD project and have 30 or so boards made. (I have no idea what a good starter project would be.) If anyone has done this, are the board costs less than thru-holes boards? Also, are Mouser and Digikey the likely source for large (e.g., 1206) parts or do you know of a better source.

Thanks!

Jack, W8TEE


Re: Second batch of uBITX shipping? #ubitx

Jim Sheldon
 

I ordered my 2nd one on 23 December, 2017 and I received information from HF Signals that it would be in about 2 weeks before it shipped and they apologized for the delay. As fast as the pre-orders (2nd group) sold out, mine could maybe even be in a 3rd group - I'll see what the serial# is when it arrives near the end of February - LOL.

Jim - W0EB

------ Original Message ------
From: "Nigel G4ZAL" <nigel@...>
Sent: 1/25/2018 2:37:24 AM
Subject: Re: [BITX20] Second batch of uBITX shipping? #ubitx

Yes, as per my first (top) post - late on 13th Dec 2017

Nigel

Re: uBitx TX performance with frequency

KD8CGH
 

Thanks all.
I'm not looking to stun pigeons, but it would be nice to have 5 watts on 30, 20 and higher if the solar activity ever picks up.
There is also a RD16HVF1 discussion in the "irf520 vs irf510" topic https://groups.io/g/BITX20/message/39265
It looks like that may be the best solution.

Alex - Thanks, please let the community know how the higher bands turn out.

    Bob   KD8CGH

Re: Second batch of uBITX shipping? #ubitx

chris gress <Chrisg0wfh@...>
 

I ordered mine 31dec mine will come with the easter bunny hopefully with more up to date software been as the first run was betas chris

On 25 Jan 2018 13:21, "Jim Sheldon" <w0eb@...> wrote:
I ordered my 2nd one on 23 December, 2017 and I received information from HF Signals that it would be in about 2 weeks before it shipped and they apologized for the delay. As fast as the pre-orders (2nd group) sold out, mine could maybe even be in a 3rd group - I'll see what the serial# is when it arrives near the end of February - LOL.

Jim - W0EB

------ Original Message ------
From: "Nigel G4ZAL" <nigel@...>
Sent: 1/25/2018 2:37:24 AM
Subject: Re: [BITX20] Second batch of uBITX shipping? #ubitx

Yes, as per my first (top) post - late on 13th Dec 2017

Nigel


Multi band Radiuno V2.0xz

Steve MW0KST
 

I'm using V2.03 on my bitx40 with great results. With all the nice features, I was thinking about adding an extra band or two or even more to the rig. 

Would it be feasible to add multi band options to the Raduino 2 software? It would keep the same IF shift etc but have extra controls for band up / down and to switch in the different BPFs / LPFs? It would also need to reverse the BFO side for USB / LSB for bands above the IF I guess. 

Any my advice would greatly appreciated!

Many thanks,

Steve MW0KST

Re: uBitx TX performance with frequency

K9HZ <bill@...>
 

This may be a futile attempt if the intermediate gain stages (pre-driver and drivers) fall off with frequency too.  I have not done this myself yet… still on my list… to actually publish a table showing the output at each stage with frequency to determine what needs attention BEFORE the PA.  Then a change to the PA makes full sense.

 

 

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com

Like us on Facebook! facebook icon

 

 

email:  bill@...

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Alex Buurlage
Sent: Thursday, January 25, 2018 3:37 AM
To: BITX20@groups.io
Subject: Re: [BITX20] uBitx TX performance with frequency

 

Bob,

Yes, I've seen similar behaviour on my homebrew uBitx. Increasing the drive will overload the PA at 80 meters but will hardly increase the power output at the high bands. I even made a change in the driver circuit that decreases the gain below 10MHZ so I could crank up the overall gain of the TX chain more trying to get more output at 14MHz and up. No success. After extensive experiments I've decided to replace the IRF510's with RD16HHF1 mosfets (not pin-compatible!).

I am now optimizing the output transformer and impedance levels but so far the TX power ranges from 10 watts at 80m to 8 watts at 17m. The 15m and up LPF is not finished yet, but reviewing the specs of the RF16HHF1 I don't expect much further power drop at 28 MHz.

Secondly I like the idea of the housing of these mosfets being the source, so a direct grounding to the case is easy. No insulation material needed and a better RF ground.

A slight disadvantage is that the bias current of the RD16HHF1 is a little higher, but that's ok for me.
If you should make such a change with the commercial PCB version, beware of the pin incompatibility.

73, Alex
PA1FOX

Re: uBitx TX performance with frequency

K9HZ <bill@...>
 

The simple way to do this is to do what Hans did on the 5W PA he produces at QRP-Labs…. There is a second set of pads on the PCB that has the right pinout for the RDxx devices.  That way you can easily use either.  So if there is a V2 of the uBITx main board it is something to consider.

 

 

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

 

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

 

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it: www.VillaGrandPiton.com

Like us on Facebook! facebook icon

 

 

email:  bill@...

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Lawrence Galea
Sent: Thursday, January 25, 2018 4:01 AM
To: BITX20@groups.io
Subject: Re: [BITX20] uBitx TX performance with frequency

 

Farhan

I know it will increase the price, but how about switching over to the RD16HVF1 which would allow the rig to run from 12V doing away with those wanting more power to increase the voltage to the PA?

Would also do away with the PA heatsinks if the case is metal and it is used as the heatsink.

Regards

Lawrence

 

On Thu, Jan 25, 2018 at 6:23 AM, Ashhar Farhan <farhanbox@...> wrote:

You can increase drive with the preset of the predriver.

- f

 

On 24 Jan 2018 6:24 pm, "KD8CGH" <rkayakr@...> wrote:

I took some time to measure the actual performance of my uBitx with its original calibration against a dummy load. The instruments used are not lab calibrated. I did check my wattmeter against my recently factory calibrated K3 and found the power reported to be about 5% high. The power supply is rated as 25 amps and set at 13.7 volts. I tested by simply pressing the PTT (no audio input, power out 0) and keying CW.
Receive current: .25 A

 

PTT

CW

CW

f kHz

I amp

I amp

P watt

3,530

0.74

1.8

8

3,970

0.74

2.1

9

7,030

0.73

1.57

5

7,270

0.7

1.6

5

10,113

0.72

1.22

3

14,030

0.71

1.34

3

14,320

0.71

1.37

3

21,170

0.69

0.96

1

28,900

0.69

0.83

0.5


The results agreed in general with Dave's (WI6R) post https://groups.io/g/BITX20/message/39578, although his results start a bit higher and end even lower.
Although my current draw with PTT down agrees with the value specified on the Tune-up page, I never quite see 10 watts out. The 80 meter power isn't too bad, but the 14 MHz is half and 28 MHz is 1/4 of that mentioned on the uBitx web page.

What TX performance have others seen?
Any fixes for higher frequencies?

     Bob   KD8CGH

 

Re: uBitx TX performance with frequency

Xcott Craver
 

Hi,

I tried the uBITX with FT-8 on 20m, and I could easily hit 5W out and probably higher.  I've observed that typical SSB usage doesn't come close to CW output power, but the signals coming out of WSJT-X can outdo CW.

This is on a QRP wattmeter that also isn't precisely calibrated.  

Thanks, Xcott K2CAJ