Date   
Re: uBITX Mic Wireup

Shaun
 

" If you tear a lot of communication mics apart you will see that the mic element is wired through the PTT switch on most of them."

That is exactly what I would expect and have seen in the past, but again, the mic wire up I saw on an earlier post for an older version did have the PTT as a separate circuit, not wired serially with the electret. While it doesn't address the mic wire up specifically, the wiring diagram for the uBITX from the website seems to suggest the same, PTT and mic are two separate circuits. I think you have confirmed my original way of thinking of how I should wire it up, i.e. closure of the PTT switch applying ground to the MIC- side of the electret, and is the way I will go.  I am using an old HT spkr\mic and going that route just means I need to move one connection point internally and I'm where I need to be. Thank you for the assist, Tim

Shaun
KEØNLN

On Fri, Mar 9, 2018 at 3:14 PM, Tim Gorman <tgorman2@...> wrote:
Jerry,

Having a live mic with a separate, unassociated PTT switch can lead to
inadvertent transmissions if the PTT gets operated accidentally. If the
mic is not live all the time then all you transmit on an accidental PTT
operation is a suppressed carrier which hopefully won't bother anyone.

It doesn't happen a lot but it *does* happen. Someone accidentally
pushes his foot switch with a live mic and sends out a discussion with
the wife (spouse) over the air.

Admittedly you can butt transmit with a PTT CB mic or 2-meter ham mic
if you sit on it. It happens also.

For me, the switch is there in the mic and I don't see any reason not
to use it. If you tear a lot of communication mics apart you will see
that the mic element is wired through the PTT switch on most of them.
Apparently someone thinks its a good idea!

tim ab0wr

On Fri, 09 Mar 2018 07:54:26 -0800
"Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> wrote:

> How is this an advantage?
>
> On Fri, Mar 9, 2018 at 07:23 am, Tim Gorman wrote:
>
> >
> > The mic is only actually connected when the PTT switch is
> > pushed. ....   This is why I recommend using a communications mike
> > instead of a standalone mic with a separate PTT switch.





Re: tx pop

John Pieper
 

Pete,

Maybe some more experimentation with the capacitor value is needed. The diode has some finite forward resistance so it will take some small amount of time for the cap to charge up. I originally had the circuit connected to U1 input as well and had settled by experiment on 330 nF. Didn't see any change in effectiveness when I moved it to M2. So maybe a somewhat smaller capacitor will fix it. (Don't remember what I have for the resistor, btw). Also by the way, my gate circuit is slightly different. I have only the diode in series with the T/R signal going to the gate. Both the capacitor and resistor are connected from the gate to ground. I seem to remember that I had a hard time getting it to work until I tried it this way. Don't know what difference it might make, though.

For R70, I knew I wanted something larger than 10 ohms to have the voltage divider produce enough output, but not so large that the maximum volume available from the volume pot would be reduced significantly. I saw that I had the 510 ohm part and thought, "try this". Simple as that.

73, John

Re: RD16HHF1 power curve flattening...some

K9HZ <bill@...>
 

Nice… any power to it yet?

 

 

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

 

Moderator – North American QRO Yahoo Group.

 

email:  bill@...

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Nik VK4PLN
Sent: Friday, March 9, 2018 2:35 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some

 

Mods so far, in tested. 


Virus-free. www.avg.com

shipping update

John KG9DK
 

I received my uBitx today

ordered January 8, 2018
notice of being shipped March 6, 2018
received March 9, 2018

john kg9dk

Re: The issues of the TDA2822

w7hd.rh <w7hd.rh@...>
 

This is the modification I came up with to implement a 7805 to supply the TDA2822.

Please check it over for errors.  One trace cut and scrape a little off the board and solder in the 7805.

Ron W7HD

On 03/09/2018 06:41 AM, Raj vu2zap wrote:
Skip,

For me obsessed in experimenting with receivers, the audio parts graduated from LM380 then smaller 386 and then someone
mentioned the TDA2822.. I always had a soft corner for National Semi but switched to TDA. I always worked on 12V and
the TDA in bridge mode. Compared to 386 the 2822 sounded warm and nice lows with 2W out.

Vaguely I remember blowing one to reverse polarity supply. One TDA melted my solderless bread board but survived. I now realise
that it IS designed for 9V or lower although it can take 15V max.

Raj

At 09-03-18, you wrote:
Raj, when you use the TDA 2822 in other designs what voltage are you running them at? Is it at the 9 volt dc via a voltage regulator?

Skip Davis, NC9O
--
W7HD - NAQCC#7587 OMISS#9898 KX3#6966 LinuxUser#415320

Re: The issues of the TDA2822

K9HZ <bill@...>
 

Works...


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!

Moderator – North American QRO Yahoo Group.

email: @Doc_Bill

-----Original Message-----
From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of w7hd.rh
Sent: Friday, March 9, 2018 7:33 PM
To: BITX20@groups.io
Subject: Re: [BITX20] The issues of the TDA2822

This is the modification I came up with to implement a 7805 to supply the TDA2822.

Please check it over for errors. One trace cut and scrape a little off the board and solder in the 7805.

Ron W7HD


On 03/09/2018 06:41 AM, Raj vu2zap wrote:
Skip,

For me obsessed in experimenting with receivers, the audio parts
graduated from LM380 then smaller 386 and then someone mentioned the
TDA2822.. I always had a soft corner for National Semi but switched to TDA. I always worked on 12V and the TDA in bridge mode. Compared to 386 the 2822 sounded warm and nice lows with 2W out.

Vaguely I remember blowing one to reverse polarity supply. One TDA
melted my solderless bread board but survived. I now realise that it IS designed for 9V or lower although it can take 15V max.

Raj

At 09-03-18, you wrote:
Raj, when you use the TDA 2822 in other designs what voltage are you running them at? Is it at the 9 volt dc via a voltage regulator?

Skip Davis, NC9O

--
W7HD - NAQCC#7587 OMISS#9898 KX3#6966 LinuxUser#415320






---
This email has been checked for viruses by AVG.
http://www.avg.com

Re: uBITX Mic Wireup

Tim Gorman
 

Shaun,

The ubitx doesn't have a balanced mic input, i.e. mic leads that don't
have one connected directly to system ground. In a balanced feed the
shield wire would be the system ground and would act as a shield to both
mic wires. Ideally in such a case the PTT would probably also have two
leads, a plus and minus, although many times the shield is just used as
the ground lead.

The PTT shouldn't be wired serially with the mic, both just use a
common ground. When the PTT is pushed the PTT switch closes the PTT
lead to the shield, i.e. system ground. At the same time the mic lead
from the element is connected to the mic lead in the cable. The minus
mic lead is connected solidly to the shield, i.e. system ground.

If the ubitx ran more power it might be necessary to take more care
with the mic circuitry. At 10-15 watts it just isn't necessary as long
as the wires inside the cabinet are dressed properly and kept away from
the PA section of the circuit board.

If you'll download the operating manual for the ftdx-3000 from the
Yaesu site and look at the page with the connector wiring, you'll see
on the microphone connector that there are two mic leads that are
separate from system shield. In fact there is even a totally separate 5v
lead for powering an electret element. Yaesu expects there to be a
blocking capacitor on the mic lead to isolate the 5v from the radio mic
circuit.

tim ab0wr


On Fri, 9 Mar 2018 18:04:27 -0600
"Shaun" <slong682000@...> wrote:

" If you tear a lot of communication mics apart you will see that the
mic element is wired through the PTT switch on most of them."

That is exactly what I would expect and have seen in the past, but
again, the mic wire up I saw on an earlier post for an older version
did have the PTT as a separate circuit, not wired serially with the
electret. While it doesn't address the mic wire up specifically, the
wiring diagram for the uBITX from the website seems to suggest the
same, PTT and mic are two separate circuits. I think you have
confirmed my original way of thinking of how I should wire it up,
i.e. closure of the PTT switch applying ground to the MIC- side of
the electret, and is the way I will go. I am using an old HT
spkr\mic and going that route just means I need to move one
connection point internally and I'm where I need to be. Thank you for
the assist, Tim

Shaun
KEØNLN

On Fri, Mar 9, 2018 at 3:14 PM, Tim Gorman <tgorman2@...> wrote:

Jerry,

Having a live mic with a separate, unassociated PTT switch can lead
to inadvertent transmissions if the PTT gets operated accidentally.
If the mic is not live all the time then all you transmit on an
accidental PTT operation is a suppressed carrier which hopefully
won't bother anyone.

It doesn't happen a lot but it *does* happen. Someone accidentally
pushes his foot switch with a live mic and sends out a discussion
with the wife (spouse) over the air.

Admittedly you can butt transmit with a PTT CB mic or 2-meter ham
mic if you sit on it. It happens also.

For me, the switch is there in the mic and I don't see any reason
not to use it. If you tear a lot of communication mics apart you
will see that the mic element is wired through the PTT switch on
most of them. Apparently someone thinks its a good idea!

tim ab0wr

On Fri, 09 Mar 2018 07:54:26 -0800
"Jerry Gaffke via Groups.Io" <jgaffke=yahoo.com@groups.io> wrote:

How is this an advantage?

On Fri, Mar 9, 2018 at 07:23 am, Tim Gorman wrote:


The mic is only actually connected when the PTT switch is
pushed. .... This is why I recommend using a communications
mike instead of a standalone mic with a separate PTT switch.



Re: Variable power control

John Backo
 

Good thought, Marco.

But most. if not all variable VR's have a fixed or lesser
VA output. IF you lower the voltage, usually the available
amperage goes down as well...

I use two in my bench supply, one with a 7815 and one
with a LM338. They work well to provide a variable voltae
but the available current is not 5A (say) for the LM338
unless the voltage is quite high. At very low voltages,
the available current is 0.5A or less.

But it is a good thought. Possibly it could be rigged
as a linear supply with 2 LM338's and a LM324 regulator...

It would be cheaper than buying separate fixed supplies.
Also cheap are variable shunt and digital supplies, but
they usually have a big RF noise problem and require
some hefty filtering..

john
AD5YE

Re: RD16HHF1 power curve flattening...some

Nick VK4PP
 

Not yet, I have decided to re-model the case, and install my RaduinoI2C board... Also mounted a swr bridge... Gonna be a nice little rig if I get reasonable results from the PA mod..
73..

Re: Fw: uBitx delivery

w2ttt <w2ttt@...>
 

Ordered mine on January 9th and it arrived in W2-land via DHL on March 9th.
73,
Gordon Beattie, W2TTT

Re: Shipping notice today, ordered Jan 12 #ubitx

Rob Snow
 

Thank you...Jan 18 is getting closer!  My 7 and 9 year old helpers are getting eager to "talk to someone" and not just lookup WSPR spots on the globe.  Sadly, my 12yr old asked "do you 3 really think that is fun?"

Rob
AG5OV

Re: Pulling Arduino data apart

Tom Christian
 

Great discussion from my perspective.  No wasted bandwidth here.  Thanks Jack & Jerry!
Tom
AB7WT

Re: uBITX Mic Wireup

Dave Bottom <ars.kd6az@...>
 

Connecting the Mic- to ground to generate PTT is common for many handheld radios. It saves a wire in the cable.  

You’ll need to rewire the Mic and PTT SW to work with the uBITX which is exactly the way you would wire it work with most QRP radios including Elecraft’s KX2/KX3 radios.

Dave WI6R


On Mar 8, 2018, at 7:54 PM, Shaun <slong682000@...> wrote:

 Does anybody have a diagram or description of the mic wire up for the uBITX? I am looking for the mic itself, not the mic jack on the transceiver. Most of the mic's I have dealt with have the MIC+ going to one side of the electret and MIC- or ground routing through the PTT switch when it is closed, completing the circuit. Looking at the uBITX schematic and a mic wireup for an older version of BITX from several years ago on the forum, what I think I am seeing is that the sleeve is providing a constant ground to both the MIC- side of the electret and one side of the PTT switch. The tip connects a constant output to the other side of the PTT switch and the ring is providing a constant output to the MIC+ side of the electret. It almost looks like the electret is an "always on" state but the output is not utilized until the separate PTT circuit is completed. Any help would be appreciated.

Shaun
KEØNLN

Re: Pulling Arduino data apart

Michael Hagen
 

All this talk about injun's puts Mikey's brain on warpath!

 


On 3/9/2018 10:10 PM, Tom Christian wrote:
Great discussion from my perspective.  No wasted bandwidth here.  Thanks Jack & Jerry!
Tom
AB7WT

-- 
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID  "MotDog@..."
Mike@...

Re: Fw: uBitx delivery

Nick Trollope
 

I have just received my notification from PayPal! Top result!
N.
G4FAT
 

From: Nick Trollope
Sent: Thursday, March 8, 2018 6:31 PM
To: BITX20@groups.io
Subject: [BITX20] Fw: uBitx delivery
 
 
Hello chaps,
 
Paid for a ubitx on 14 January 18. Does anyone have any idea what delivery times are like at the moment?
 
Thanks
Nick
G4FAT
 

Re: Variable power control

_Dave_ K0MBT
 

I have been powering my bitx40 with a 3s Lipo battery Nominal voltage 12.  last night I thought maybe I could put in a LM317 and set the bias for 12 v and power the radio with a higher voltage lipo. Leaving the power for the power amp at battery voltage. it would be easy enough to change batteries for different power levels.

Things didn't go quite as planned. I think some RF may have gotten into the regulator (a guess) The regulator became quite hot even though i had put on a power transistor to carry most of the load. The sensitivity of the radio was noticeably less. I stopped the experiment for now. The Bitx is my only radio and I didn't want to burn something out. . 

Re: The issues of the TDA2822

Marko Pavlicevic
 

" We finally located a source of brand new, high quality TDA2822s that are currently being shipped."

I placed an order few days ago... Does that mean that I will have normal chip that doesn't need any mods? Maybe just lowering voltage with 78L09?

Re: The issues of the TDA2822

Gary Shriver
 

That’s a great question.  Mine was shipped two days ago.  Will it come with a 7822 that won’t require any mods?
Thanx-Gary


On Mar 10, 2018, at 6:16 AM, Marko Pavlicevic <sonymlp@...> wrote:

" We finally located a source of brand new, high quality TDA2822s that are currently being shipped."

I placed an order few days ago... Does that mean that I will have normal chip that doesn't need any mods? Maybe just lowering voltage with 78L09?

Re: How to order a Raduino

clyde-alex@...
 

I would like very much to order one of these.
please email me.
I am good on qrz
--
73
clyde
kk4ywi

Re: Pulling Arduino data apart

Jerry Gaffke
 

The Wikipedia entry is a much better starting point than my previous stackoverflow conversation:
    https://en.wikipedia.org/wiki/Endianness
Also this, do a search for "endian":
    https://en.wikipedia.org/wiki/Lilliput_and_Blefuscu

Jerry, KE7ER



On Fri, Mar 9, 2018 at 01:02 pm, Jerry Gaffke wrote:

Here's a starting point on web resources regarding this big/little endian stuff in case you're curious.