Date   
Re: µBITX & QRP labs 50W PA

padmanabhan cattamanchi
 

Most of the the VU2s use a laptop smps with a bit of filtering to give nearly 20 watts out. I don't think there is a need of another amp since the devices are the same

de vu2pep 

On Tuesday, December 17, 2019, 05:28:23 PM GMT+5:30, John AE5X <ae5x@...> wrote:


At $300 the HR-50 supports the uBITX on all bands and modes. And it does not require a PTT In signal since it has a carrier-operated relay:
https://www.hobbypcb.com/index.php/products/hf-radio/hardrock-50-hf-power-amp

John AE5X

Re: New tower

GM4CID
 

Makes me think of the Led Zepplin song.

Re: HF Coupon for case

Jack, W8TEE
 

Ken:

I didn't notice that as I used it when I bought my son a Christmas gift. Still, it's a pretty good deal.

Jack, W8TEE

On Tuesday, December 17, 2019, 9:12:30 AM EST, Ken Hansen <ken@...> wrote:


That $5 price is after an additional $49.95 purchase. I agree, it is a great little case - I use one to hold a DMR HT, Pi-Star hotspot, USB battery pack for both, and a charger as a mini DMR go-box 'solution' - just add wifi and you're one the air' (so to speak).

Ken, N2VIP

On Dec 17, 2019, at 08:05, Jack, W8TEE via Groups.Io <jjpurdum@...> wrote:


All:

Harbor Freight has this coupon:

<hfCoupon.jpg>


for the small Apache case. It's regular price is $15 and often on sale for $10, but $5 is the cheapest I've seen it. I put Diz's 5 W in one:

<FigureJ(Small).jpg>

and it worked out well. I put all the connectors on the top panel so it remains watertight and still has room for paddles, earbuds, and antenna.

Jack, W8TEE


--
Jack, W8TEE
<hfCoupon.jpg>
<FigureJ(Small).jpg>
<hfCoupon.jpg>

--
Jack, W8TEE

Re: HF Coupon for case

Ken Hansen
 

That $5 price is after an additional $49.95 purchase. I agree, it is a great little case - I use one to hold a DMR HT, Pi-Star hotspot, USB battery pack for both, and a charger as a mini DMR go-box 'solution' - just add wifi and you're one the air' (so to speak).

Ken, N2VIP

On Dec 17, 2019, at 08:05, Jack, W8TEE via Groups.Io <jjpurdum@...> wrote:


All:

Harbor Freight has this coupon:

<hfCoupon.jpg>


for the small Apache case. It's regular price is $15 and often on sale for $10, but $5 is the cheapest I've seen it. I put Diz's 5 W in one:

<FigureJ(Small).jpg>

and it worked out well. I put all the connectors on the top panel so it remains watertight and still has room for paddles, earbuds, and antenna.

Jack, W8TEE


--
Jack, W8TEE
<hfCoupon.jpg>
<FigureJ(Small).jpg>
<hfCoupon.jpg>

HF Coupon for case

Jack, W8TEE
 

All:

Harbor Freight has this coupon:

Inline image

for the small Apache case. It's regular price is $15 and often on sale for $10, but $5 is the cheapest I've seen it. I put Diz's 5 W in one:

Inline image

and it worked out well. I put all the connectors on the top panel so it remains watertight and still has room for paddles, earbuds, and antenna.

Jack, W8TEE


--
Jack, W8TEE

New tower

Jack, W8TEE
 

...and my kids didn't think I could put it up myself!

Inline image


--
Jack, W8TEE

Re: Templates for China EF01 Electronic Plastic Shell Project Case for a BITX40

Mike Short
 

I used some PCB for mine. Or you can go to a hardware store and get some aluminum and make a new panel. The steel one is hard to work with. 


mike
AI4NS

Re: µBITX & QRP labs 50W PA

John AE5X <ae5x@...>
 

At $300 the HR-50 supports the uBITX on all bands and modes. And it does not require a PTT In signal since it has a carrier-operated relay:
https://www.hobbypcb.com/index.php/products/hf-radio/hardrock-50-hf-power-amp

John AE5X

Re: uBitx FT8

Ashhar Farhan
 

By August, we didn't have any v4 boards. Can you send me a picture directly to my email address?
- f

On Tue 17 Dec, 2019, 1:48 AM V Zecchinelli, <n1vin@...> wrote:
Jerry, Sarma, Gordon,

Wow, am I confused.  I purchased 12 August 2019 and I thought it was a V5 however after Jerry's response I looked and it is a V4.  My bad for not checking things better.  Live and learn.

I am using a stereo cable I bought on ebay cheap.  After your responses I decided to check the 3.5mm connectors to see if there could be a short there.  Well, there are only 2 wires in the cable and shield and ring are connected together.  Lesson, don't buy cheap cables on ebay.  I will order some quality stereo cables from Amazon and see how things go.

Thank you so much for your responses.

Vince


On 12/16/2019 12:46 PM, Gordon Gibby wrote:
Are you DC shorting out the output with a transformer in the sound card??


On Dec 16, 2019, at 12:07, Jerry Gaffke via Groups.Io <jgaffke@...> wrote:

I'd guess your USB soundcard cabling is somehow (almost) shorting out the audio from that 2822 chip.
Look for a short.
Perhaps add an 8 or 10 ohm resistor in series with the TDA2822 to protect it from shorts like that.

The TDA2822 amp was used on v3.
Some discrete transistors were used on v4.
On v5, as Sarma has stated, the trusty (crusty?) old LM386 was used.

If you have a TDA2822 chip installed, it is probably v3.
A search of the forum for 2822 will reveal that a few v3 uBitx boards went out
with a WX branded TDA2822.  This clone of the TDA2822 works fine up to about 8v,
above 8v it can sometimes self destruct.   If you have a WX branded TDA2822 on
your board, I suggest you get an NJM2073D ordered from a reputable distributor
It is pin compatible with the TDA2822, works fine, good to 15v or so.

The original TDA2822 in the DIP package from ST is no longer available,
though ST does still sell it in an SOIC.
There are a half dozen different makers of clone TDA2822's, many of them work fine.

Some of the clones work ok but only with a maximum supply voltage of around 6v.
With the WX TDA2822 clone operating at 12v in the uBitx, the chip might work fine
for weeks and then suddenly decide to blow bits of silicon across the room.


A fun bit of trivia from https://en.wikipedia.org/wiki/LM386
  "The LM386 was invented by Ernie Leroy Long at Motorola in 1969. It was originally for part of a fuel injection system for a Ford Car."

If true, I assume it went by a different name at the time.
I'm a bit suspicious, a google for "LM386 Ernie" gets many copies of exactly the above phrase with no further information or attribution.
The "LM" prefix suggests National Semiconductor, perhaps it had a different name coming out of Motorola.

Jerry, KE7ER
 

On Mon, Dec 16, 2019 at 07:10 AM, V Zecchinelli wrote:

Good Morning,

I have a quick question on FT8 with uBitx V5 using USB soundcard (7.1 Channel).  Even with the volume of uBitx set very low the 2822 audio amp gets very hot and if volume set over 1/4 it will fail catastrophically.  On phone I can listen to the radio all day with no issues.  Seems odd.  Anyone else seen this problem?

Thanks,
Vince

Re: µBITX & QRP labs 50W PA

Ashhar Farhan
 


Allison,
I am basing my report in wa2eby's recommendations. My own measurement lead me to believe that between 25 ma to 150 ma, there is not much of a difference in linearity. The linearity increases only around 500ma. By then, we are roasting potatoes.

- f

On Tue 17 Dec, 2019, 3:22 AM ajparent1/kb1gmx, <kb1gmx@...> wrote:
Farhan,

No its not.  You need to be more than 100ma to get sorta on the linear part of the IRF510 bias curves.

At minimum bias you are on the very curved part of the gate threshold curve and the IMD will be poor with
crossover distortion.  Also we are not switching as its linear from transistor to transistor its complementary.
 
---------------------------------
No direct email, it goes to bit bucket due to spam

Re: Brand new uBiTX v5.0 quality issue ?

pluto@...
 

Hi Ashhar, I agree with you.
I also wrote a serious email to hfsignals attaching several photos but they haven't given me any answer yet..

73's Diego

Re: Brand new uBiTX v5.0 quality issue ?

 

Couple of boards with me with broken pot leads.

If the pots are mounted a little higher above the pcb then they can be twisted without problem.

Raj


At 17/12/2019, you wrote:
i am treating this as a serious quality issue. have others faced this too? by twisting the trimpots, the tracks can potentially come off. please write to hfsignals@... and ask for a replacement.

- f

On Tue, Dec 17, 2019 at 3:32 AM Mike WA0YCN < mgassman@...> wrote:

Diego,

I got my board in early November and my trimmer was skewed as well. I presume they turned it like that because they changed heat sinks and the new ones go closer to the pc board than previous ones.  Regardless, I haven’t experienced any problems.Â

Just curious - my family is from Nervesa - where might you call home?

Mike

Re: Brand new uBiTX v5.0 quality issue ?

pluto@...
 

Hi Mike, thanks a lot for infos ! 
Therefore it seems that it is only an aesthetic issue. it's not very nice to look at but if it works, that's okay.

I'm from Reggio Calabria, my city is right in front of Sicily island, in southern Italy. Nervesa is located in the north, about 1200km (780 miles) away.

73's Diego

Re: Brand new uBiTX v5.0 quality issue ?

Ashhar Farhan
 

i am treating this as a serious quality issue. have others faced this too? by twisting the trimpots, the tracks can potentially come off. please write to hfsignals@... and ask for a replacement.

- f

On Tue, Dec 17, 2019 at 3:32 AM Mike WA0YCN <mgassman@...> wrote:

Diego,

I got my board in early November and my trimmer was skewed as well. I presume they turned it like that because they changed heat sinks and the new ones go closer to the pc board than previous ones.  Regardless, I haven’t experienced any problems. 

Just curious - my family is from Nervesa - where might you call home?

Mike

Re: Nextion question from new member

Philip
 

Almost. R253 replaced by a 0.1 Mfd cap.

Philip G7JUR

Re: Nextion question from new member

Curt
 

Rick

The display choice indeed is a large factor in case selection. Use your favorite search engine to query ubitx enclosure,  and check out what's being used. I am using a case from amateurradiokits.in that many are happy with.

Your v5 is nice, no must buys required. Choose your display and go from there. I suggest powering up with the stock display first.

Curt

Re: Brand new uBiTX v5.0 quality issue ?

Mike WA0YCN
 

Diego,

I got my board in early November and my trimmer was skewed as well. I presume they turned it like that because they changed heat sinks and the new ones go closer to the pc board than previous ones.  Regardless, I haven’t experienced any problems. 

Just curious - my family is from Nervesa - where might you call home?

Mike

Re: µBITX & QRP labs 50W PA

ajparent1/kb1gmx
 

Farhan,

No its not.  You need to be more than 100ma to get sorta on the linear part of the IRF510 bias curves.

At minimum bias you are on the very curved part of the gate threshold curve and the IMD will be poor with
crossover distortion.  Also we are not switching as its linear from transistor to transistor its complementary.
 
---------------------------------
No direct email, it goes to bit bucket due to spam

Re: uBitx FT8

V Zecchinelli
 

Thanks Jerry,

I purchased from HF Signals website.  Board says 948/4.  I also have a V3 labeled 0705/3.  The silkscreen on both boards says ubitx v3 (c) hfsigs.com, 2017.  On the V3 I had removed the WX chip and installed a socket and TDA2822M.  I disassembled the V3 to use the case for what I thought was a V5.

Thank you,

Vince


On 12/16/2019 3:31 PM, Jerry Gaffke via Groups.Io wrote:
A v4 with a TDA2822 chip driving the speaker/phones is still a bit confusing.

v3 had the TDA2822
v4 had a couple discrete transistors in push-pull.
v5 has the LM386

Did you buy directly from hfsignals.com on Aug 12 2019?
Or some other vendor?

Jerry, KE7ER




On Mon, Dec 16, 2019 at 12:18 PM, V Zecchinelli wrote:
Jerry, Sarma, Gordon,

Wow, am I confused.  I purchased 12 August 2019 and I thought it was a V5 however after Jerry's response I looked and it is a V4.  My bad for not checking things better.  Live and learn.

I am using a stereo cable I bought on ebay cheap.  After your responses I decided to check the 3.5mm connectors to see if there could be a short there.  Well, there are only 2 wires in the cable and shield and ring are connected together.  Lesson, don't buy cheap cables on ebay.  I will order some quality stereo cables from Amazon and see how things go.

Thank you so much for your responses.

Vince

Re: uBitx FT8

Jerry Gaffke
 

A v4 with a TDA2822 chip driving the speaker/phones is still a bit confusing.

v3 had the TDA2822
v4 had a couple discrete transistors in push-pull.
v5 has the LM386

Did you buy directly from hfsignals.com on Aug 12 2019?
Or some other vendor?

Jerry, KE7ER




On Mon, Dec 16, 2019 at 12:18 PM, V Zecchinelli wrote:
Jerry, Sarma, Gordon,

Wow, am I confused.  I purchased 12 August 2019 and I thought it was a V5 however after Jerry's response I looked and it is a V4.  My bad for not checking things better.  Live and learn.

I am using a stereo cable I bought on ebay cheap.  After your responses I decided to check the 3.5mm connectors to see if there could be a short there.  Well, there are only 2 wires in the cable and shield and ring are connected together.  Lesson, don't buy cheap cables on ebay.  I will order some quality stereo cables from Amazon and see how things go.

Thank you so much for your responses.

Vince