Date   
Re: uBitx V4 test point measurement chart #ubitx #ubitx-help

Dan Schaefer
 

TP list and values would be great. I would like one too if it exists. 
Dan. W3BU




On Jan 11, 2019, at 5:46 AM, Ted via Groups.Io <k3rta@...> wrote:

Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes?   I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

Re: uBitx V4 test point measurement chart #ubitx #ubitx-help

Albert Peter
 

The test docs will be posted on hamradiodesigns.com in a few days.

Al

 

Sent from Mail for Windows 10

 

From: Dan Schaefer
Sent: Friday, January 11, 2019 7:08 AM
To: BITX20@groups.io
Subject: Re: [BITX20] uBitx V4 test point measurement chart #ubitx #ubitx-help

 

TP list and values would be great. I would like one too if it exists. 

Dan. W3BU

 

 

 


On Jan 11, 2019, at 5:46 AM, Ted via Groups.Io <k3rta@...> wrote:

Raj, et al,

Might I please get my hands on a list or chart with TP levels, for troubleshooting purposes?   I did a search here on the forum but came up empty.

Thanks,

Ted
K3RTA

 

Re: Using a HYCAS IF amp in the BITX receiver

ajparent1/KB1GMX
 

See enclosed 73mag for some test data RE: 4109 feedback amp.
Its been the gold standard for more than a few decades.

Re: Using a HYCAS IF amp in the BITX receiver

Russ Hines
 

2N5109.  Move along. ;-)

Russ Hines
JMS & Associates, Inc.
SBE CSRE
WB8ZCC
Reply to: russ@...
On 1/11/2019 8:46 AM, ajparent1/KB1GMX wrote:

See enclosed 73mag for some test data RE: 4109 feedback amp.
Its been the gold standard for more than a few decades.

Re: MAX9814 as AGC preamp for output

MVS Sarma
 

Wayne,
 go on ebay.com and type item  292736691077

 you would get it please.
  regards
sarma
vu3zmv


On Fri, Jan 11, 2019 at 4:30 PM Wayne Leake <wayneleake@...> wrote:
 Ted, the "here" does not take me to the correct place.
 Now I am wondering.
 Best, usually, to paste in the actual URL.
 Wayne WA2YNE

Unresponsive

Jack Purdum
 

All:

I just looked in my Spam folder and found over 420 messages from this group and two others I belong to. If you asked me something and I did not respond, that's probably what happened. It should be fixed now.

Jack, W8TEE
_

Re: Case for uBITX with Nextion Display

Jack Purdum
 

On Thursday, January 10, 2019, 6:46:26 AM EST, Bob Lunsford via Groups.Io <nocrud222@...> wrote:


Check this one out:


Bob — KK5R

--------------------------------------------
On Wed, 1/9/19, Doug Person <doug@...> wrote:

Subject: [BITX20] Case for uBITX with Nextion Display
Date: Wednesday, January 9, 2019, 9:54 PM

I'm wondering if anyone has identified a good
case for uBTIX with enough
room for a 3.5" or bigger Nextion
display.

I've been browsing around - but I'm
just not sure what would work.  Ideas?

--
73 de Doug -- KJ0F






Re: JackAl Encoder question...

Jack Purdum
 

Other than putting another hole in the faceplate, I don't think it would be a bad idea to use encoders w/o the push button switch. The reason is because some encoders have a stiff switch, which requires you to hold the µBITX case since it doesn't have enough mass to sit still. (Place one of those little mats that you use to untwist jars under the µBITX helps keep it in one place.) A NO SPST push button could be used, and just run it to the pin reserved for the encoder switch, or use an open I/O pin. If anyone does this, report back here and lets us know what you think.

Jack, W8TEE

On Wednesday, January 9, 2019, 1:45:59 PM EST, PeteWK8S via Groups.Io <pmeier@...> wrote:


The main encoder does not have a pushbutton but I still intend to add the second fine-tune encoder which does have a push button.

As for isolating the headphone jack I'm using an enlarged hole and thin, clear plastic washer to insulate the jack's round nut. That plus paint in and around the hole should do just fine.

Re: ND6T AGC Troubleshooting

Don, ND6T
 

What is the voltage on the base of Q1? What signal source are you using when you see no voltage output? Are you measuring at the junction of C3, R3, the cathode of D2, and the gate of Q2 to ground? Did you measure the resistance from the other side of that pot to the point that you are using for ground? 73, Don

Re: Harmonics and Relay Replacement

Jerry Gaffke
 

Spoiler alert!















I mean that if not staged, she would soon be nursing some nasty 3rd degree burns.
Of course, I've never done anything like that.  ;-)

Jerry


On Fri, Jan 11, 2019 at 04:05 AM, Bill Cromwell wrote:
You mean the complete lack of any solder or other tools anywhere in the photo? Shouldn't there be *something* in her other hand? And where is the solder smoke? I noticed all of that *after* I noticed she really is a pretty girl just as the label says:)

Re: uBitx V4 test point measurement chart #ubitx #ubitx-help

Ted
 

Good day, Raj.

A DC chart would be great.  What I have for diagnostics besides a few good DVM's are a dual-trace oscilloscope, an audio signal tracer, a single tone source, and another HF radio. Back when I worked in a business-radio shop with a proper service monitor, a popular trick was to take a piece of RG-58 from the instrument's RF input and put about a 20mm loop of the inner conductor folded around and back to the shield as a "sniffer". That's what I've done to find the last place the signal appears with any noticeable force at all.  Crude, but effective. Without knowing what I should see at Q90 and beyond, I'm basically just guessing. 

Nothing is obviously burned or exploded except my self-respect at this point!


Thanks,
Ted
K3RTA

Re: uBitx V4 test point measurement chart #ubitx #ubitx-help

Ted
 

Outstanding.  Looking forward to it. Thanks.

-Ted

Re: JackAl Encoder question...

bands11
 

I’ve got several BITX varieties and I’ve put standalone pushbutton switches on every one.  It’s great to be able to just push the button instead of anchoring my BITX with one hand and pushing the encoder switch with the other.  I simply wired them in parallel so I keep all the functionality as well.

Bob, KE7QEQ


On Jan 11, 2019, at 8:19 AM, Jack Purdum via Groups.Io <jjpurdum@...> wrote:

Other than putting another hole in the faceplate, I don't think it would be a bad idea to use encoders w/o the push button switch. The reason is because some encoders have a stiff switch, which requires you to hold the µBITX case since it doesn't have enough mass to sit still. (Place one of those little mats that you use to untwist jars under the µBITX helps keep it in one place.) A NO SPST push button could be used, and just run it to the pin reserved for the encoder switch, or use an open I/O pin. If anyone does this, report back here and lets us know what you think.

Jack, W8TEE


Veni vidi visa ... I came, I saw, I charged!


Re: ND6T AGC Troubleshooting

WA6PXC Rich <sigma@...>
 

Hi Curt,
I have tried a number of the AGC circuits floating around out there.
They all seem to work, but do not handle large (>1000 microvolts) signals.
Out of frustration, I have developed an AGC controller which controls the RF path
instead of the audio path. It begins to control the signal at about 30 uv and continues
to provide very good control up through about 7000 uv.
It essentially uses a BS170 FET in place of R12.
I have a neighbor 2 blocks away running 500 watts on 40 meters. His signal is not distorted
now...
If you are interested I can lead you through the process of building one...
Kind Regards..
Rich

-----Original Message-----
From: "Curt via Groups.Io"
Sent: Jan 10, 2019 6:54 PM
To: BITX20@groups.io
Subject: [BITX20] ND6T AGC Troubleshooting

I am beside myself that I cannot get this simple circuit doing something with the ubitx.  I am starting with the simple version with a single MOSFET, and I may add the series one later. 

I built one unit - nada.  So I build a second one, and left off the MOSFET.  I have its input attached to high side of the volume control pot (I think it is 10k in the Sunil case version), the ground attached to a connector in the closest corner of the board, and 5 volts from the raduino.  No matter how huge the signal -- I get no rectified voltage output.  What could I be doing wrong?  With hundreds of these boards in uBITX I am surprised by my result thus far. 

I am using a 2n2222A for the NPN, I have tried 3 different devices.  Yes the diodes each work on the DVM, and they are proper orientation. 

I also could not get the VK3YE AGC to work either.  The ubitx receives wonderfully and I am testing on 40m. 

73 Curt

PS - I do have a hybrid cascode but I am thinking to use it in a homebrew Rx -- not sure I wish to 'break' one of the bidirectional amplifiers here.  my goal is just to AGC the very largest signals. 

Re: MAX9814 as AGC preamp for output

Ted
 

Hi, Wayne.

My apologies inasmuch as the hyperlink didn't embed correctly. This was what I used, though not ideal -

https://www.ebay.com/itm/MAX9814-Electret-Microphone-Amplifier-Module-AGC-Auto-Gain-Control-for-Arduino-/272290839552

Lots of vendors sell those ^.  The other gentleman had shown one of these other boards, or similar -

https://www.ebay.com/itm/Microphone-Amplifier-Electret-MAX9814-perfection-with-AGC-Features-For-Arduino/253379344340 

........and if I were to start over, I'd have used the latter of the two simply because it's better suited for this kind of work.   Give it a run.

Re: Case for uBITX with Nextion Display

Ted
 

Until you add the shipping.  Ebay - Free   Banggod - $5+  and both are on the slow boat from, well..........

Re: Harmonics and Relay Replacement

iz oos
 

She's complaint..


Il 11/gen/2019 17:53, "Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> ha scritto:
Spoiler alert!















I mean that if not staged, she would soon be nursing some nasty 3rd degree burns.
Of course, I've never done anything like that.  ;-)

Jerry

On Fri, Jan 11, 2019 at 04:05 AM, Bill Cromwell wrote:
You mean the complete lack of any solder or other tools anywhere in the photo? Shouldn't there be *something* in her other hand? And where is the solder smoke? I noticed all of that *after* I noticed she really is a pretty girl just as the label says:)

Re: Harmonics and Relay Replacement

Jerry Gaffke
 

For those not sure where this thread is coming from, here's the photo in question:
    https://groups.io/g/BITX20/message/63764


On Fri, Jan 11, 2019 at 08:53 AM, Jerry Gaffke wrote:
Spoiler alert!

Re: ND6T AGC Troubleshooting

Curt
 

Don

reply gratefully appreciated. 

base is biased at 0.67 volts, and collector is at 5.07 volts as the raduino supply.  so this looks okay in terms of biasing the transistor. 

I have the rig plugged into a MA8040 vertical with a nice radial field here on the east coast.  I tune across 40m and look for huge signals.  A loud SSB, or much higher a shortwave broadcast has me cranking the volume down as low as it can go to stand it with headphones. 

resistance across the volume control pot is 9.9 k ohms, and I get same value when I touch the screw at the corner of the main board. 

At this point, in the circuit installed - I only have a 100k resistor and a 2.5 uF capacitor (non-polarized, I measured it to confirm) loading the output of the rectifier.  I built this board as a take 2, the other one is behaving similar with a MOSFET installed. 

the diodes each measure around 0.58 on diode setting of my DVM.  They seem to be diodes. 

Curt

Re: Harmonics and Relay Replacement

Doug W
 

so we're not entertaining any ideas that she could be some kind of self repairing cyborg/cylon/android/terminator?
--
www.bitxmap.com