Date   
Re: Rx Radio #ubitx-help

Mike aka KC2WVB <rb5363@...>
 

Exactly!

I know our language difference made this take a while to get to the root of things because not being a native English speaker you selected words that were not well defined enough to strictly express your question but hats off to you because I don't speak your native language at all.


On Fri, Jun 22, 2018, 3:50 PM sridhar <vu3pen@...> wrote:
Mike

thx for tech inputs , yes i got the details from this post 
AM allows for 5KHz of audio and SSB allows for roughly 2.7 to 3 KHz of audio
to change this filters required 

thx 
de
vu3pen
sridhar 

Re: Rx Radio #ubitx-help

sridhar
 

Mike

thx for tech inputs , yes i got the details from this post 
AM allows for 5KHz of audio and SSB allows for roughly 2.7 to 3 KHz of audio
to change this filters required 

thx 
de
vu3pen
sridhar 

Re: Somethings gone wrong!

M0CLS
 

I’m suspecting the 10ohm resistor R43. I’m not experienced at all with smd and perhaps I ruined it with my iron. I only have a 47ohm replacement. I will replace with that and see where I get. I can’t see it being the problem with the drop in power and mic audio level though... 

Carl.

Re: experience with Sunil VU3SUA's enclosures #ubitx

Mike aka KC2WVB <rb5363@...>
 

I paid for my case from Sunil through a Discover card and honestly can't remember if they sent a confirmation that the order was created. I tried to look it up in my gmail history but my history self deleted whatever might have been there.
None the less my case arrived about 3 and 1/2 weeks after the order was placed and it was well worth the wait. Its very, very nice. I would try an email or wait and see. After all we are not talking about a lot of dough for the case and I would not want to chance not getting it.

On Fri, Jun 22, 2018, 12:17 AM Mike KK7ER <groupio@...> wrote:
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: Microscope - - new thread

Roy Appleton
 

That's the same thing you'd get from Banggood but a few dollars more and of course you'd get it a few weeks sooner also! :-))

Roy
WA0YMH

On Fri, Jun 22, 2018, 1:22 PM Gwen Patton <ardrhi@...> wrote:
Here's the one I got:

https://www.ebay.com/itm/600X-4-3-Portable-Display-Electronic-Digital-Video-Microscope-LED-Magnifier-S2X9/123142757131?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

It's not fantastic, but it's still more usable than what I had.

Re: Rx Radio #ubitx-help

Mike aka KC2WVB <rb5363@...>
 

Sridhar, I understand your post now. Your not asking how to receive AM broadcast signals rather your asking how to improve the audio quality of the AM signals your receiving. Right?

If you think about the difference between AM and SSB audio that is mixed with a carrier to create the hetrodynes that radiate over the air then what is notable is that AM allows for 5KHz of audio and SSB allows for roughly 2.7 to 3 KHz of audio. The reason for the difference is the power is, in a sense, more concentrated with respect to the SSB signal and it will travel further for an equal amount of total power. Hence your reciever has a narrower filter than an AM radio's reciever because it does not need to hear 5KHz to the left and right of the carrier. 

The downside is that when you use the SSB reciever to listen to AM broadcasts the audio will not be as full bodied as it would if the filter was wider. If you want to change the filter you would have to isolate the parts of the radio that form the filter and make the necessary changes. If you did, it would not be a bad idea to make the filter selectable as in most modern all-mode receivers so that you can select what is best for CW, SSB and finally AM. 

For myself, I am not that picky and listen to AM with the SSB filter if for no other reason than its a lot of work to bring about such a change. So, I can't tell you precisely what other than the filter would need altered.

On Fri, Jun 22, 2018, 4:43 AM sridhar <vu3pen@...> wrote:
I had ubitx ,currently using for RX Only ,its my first HF set ,Ubitx having 3 Mhz to  30 Mhz Frequency ,
1)Can i use this for Normal Radio RX i.e SW , i am able here radio but audio is not able to recognize. 
2)  what changes do need to do in this set to added any component to get full audio from SW frequency 



de 
vu3pen
sridhar 

Re: Microscope - - new thread

Michael Maiorana
 

The "Solderscope" idea is brilliant. That's next on my (ever expanding) list.
You guys are too clever. Slow-pokes like me can't keep up. I just finished my NC40a :)

Mike M.
KU4QO

On Thu, Jun 21, 2018 at 5:23 PM, T Williams via Groups.Io <n41w124@...> wrote:
Re: #52380 "Seems to me you could DIY something better than those
$60 Chinese special microscopes ... "

Consider a SolderScope. (See QRP Quarterly, Apr. 2018.) (www.qrparci.org
Its a DIY binocular stereo inspection microscope for about $50.

Get a pair of 3.5X - 420mm dental magnifying loupes for $30 or so from Ebay/
Amazon.  Add +2 reading glasses in front of the loupes. (Dollar store readers
work OK.) Mount the loupes on a desk lamp stand.

I built the first SolderScope almost 2 years ago and use it daily while the
AmScope SE-400 sits unused. Advantages of the SolderScope are low cost, wide
field, 7 inch working distance and I can keep my eyeglasses on.

Web page at http://www.qsl.net/k9ac/solderScope.html has full details.

73,

Tom Williams,  K9AC


Re: Understanding Spurious Emissions

Jerry Gaffke
 

Correction:  use the step attenuator to reduce the strength of your main signal FROM the dummy load 
You likely want a pretty serious resistive divider between dummy load and step attenuator,
The step attenuator might be able to disspate a Watt, maybe less. 


On Fri, Jun 22, 2018 at 09:58 am, Jerry Gaffke wrote:
Then tune in your operating frequency, and use the step attenuator to reduce the strength of your main signal
into the dummy load until you get the same S-meter reading as you did for the spur.

Re: Oscilloscope on sale

Michael Hagen
 

Yes, I got the Siglent SA, and sold the old Rigol on eBay.

What a difference.  So Rigol and Siglent are at the top of my list.

And remember the 2 day discounts by Circuit Specialists, usually 15% can be significant on a big purchase.

I would go for a bigger screen the on the Rigol scope.

And yes, the 100 MHz upgrade on the internet worked perfectly.

I am glad they are now just unlocking things.  Hiding features for Ransom seems kind of counter productive

to good bossiness practices?


Mike, WA6ISP


On 6/22/2018 9:06 AM, R. Kuehn wrote:
Just to throw another good scope in the mix is the Siglent 1202X-E for $380. 2 channels, 200MHz all the bells and whistles come unlocked, no hacking necessary. A great scope, I love it.

Eevblog did a review about a year ago, 

Ralph
N9WTX

On Fri, Jun 22, 2018 at 10:52 Ralph Mowery <rmowery42@...> wrote:

I have seen on youtube where some have flashed the software in some of the scopes and other devices to raise them up to higher levels.  There may or may not be some small components in them that limit the bandwidth so you may not be able to get the traces to show a true waveform at the higher frequency.

At the least you would have o get better probes for the scope.

The Hanteck 200 mhz scope I have does not seem to do the XY patterns very well.  I have to drop back to my old Tectronic analog to do that.  Maybe a better quality digital scope will do the XY patterns better than my inexpensive Hanteck

de ku4pt





On Fri, Jun 22, 2018 at 11:26 AM, Michael Hagen <motdog@...> wrote:

I got my Rigol on eBay, new just a few hours.  DS1054 for about $370.  Had to do the 100MHZ operation.

They have newer ones now, better, but more $.


I like it, but for the price I think the Hantek 200 MHZ is a better deal, especially since Jack likes his.

Circuit Specialties has sales once in a while, I got 15% off my Spectrum Analyzer from them.

I had problems with the Hantek USB scopes, did not like them.   I would never buy a PC connected scope again.

I seldom use more than 2 channels?

The Rigol is actually TOO SMALL.  Too many features and screen is small, I can't see all the stuff.


Strange, my Rigol  has 1 flaky probe already, AND the Ground Alligators take BIG Muscle to open!

They sure have a real spring in there!  They surprise me every time I clip.

Mike, WA6ISP



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

Re: Oscilloscope on sale

sebastian ulloa <sightes@...>
 

Ok

El 22 jun. 2018 14:24, "Bo Barry" <wn4ghv@...> escribió:
I read there is a software hack to extend its HF response. Haven't tried it yet.


Re: Oscilloscope on sale

Bo Barry <wn4ghv@...>
 

I read there is a software hack to extend its HF response. Haven't tried it yet.

Re: Microscope - - new thread

Gwen Patton
 

Re: RF Situation Resolved.

Latham, Chip
 

Make sure you are using an insulating kit including the screws and the back either mica or other insulator. No continuity between the gates after mounting the irf510's
Using the insulating mounts you wont have to worry about the 12DC being shorted to ground by accident if using a metal case. Since the IRF510 are 180 degrees out of phase if they short on the heat sink you will blow them, like I did.
Hope that helps

Re: Homebrew from scratch #ubitx

Peter Carr
 

I have just built a uBITX with standard components (no SMD's) from scratch on a PCB I designed - it works well.  I have now designed another PCB which incorporates the Arduino NANO and the the Si5351 shield and I'm just waiting for the PCB's to arrive and then I will start assembling.  I made some changes to the circuit to allow for a dynamic microphone and the use of screened TOKO cols for the 30MHz lowpass filter, I also changed the coupling arrangement to the 45MHz filter.

I have attached a picture of the original PCB and a PDF of the new layout incorporating the Arduino and Si5351

Maybe one day I will play with SMT but for now standard components are still easily available !
 
73's - Peter M0HYT

Re: RF Situation Resolved.

M Garza <mgarza896@...>
 

One big heatsink is fine, as long as both FETs are insulated from it.

I plan on doing this, once I get to putting things in a case.

Marco - KG5PRT 


On Fri, Jun 22, 2018, 12:14 PM <hotrod541@...> wrote:
I just need some clairifaction on replacing the heat sinks on uBITX.  I am in the process of maching out a new heat sink, which will be one piece.  If I am correct,  if I mount each FET with the correct mounting pads and they don't touch they should work fine or am I missing something here.  I just don't want to manufacture a problem. 
Thanks, 73
Buddy, KJ4ZSI

Re: RF Situation Resolved.

hotrod541@...
 

I just need some clairifaction on replacing the heat sinks on uBITX.  I am in the process of maching out a new heat sink, which will be one piece.  If I am correct,  if I mount each FET with the correct mounting pads and they don't touch they should work fine or am I missing something here.  I just don't want to manufacture a problem. 
Thanks, 73
Buddy, KJ4ZSI

Re: W8TEE Power/SWR Sketch for Nano

Kees T
 

That's the one. We're putting together a 25mW to 25W Power SWR meter (.....like who isn't) and have a great bidirectional coupler, the AD8307s, some Op-Amps as needed for level control and calibration, a Nano, and several of those displays. Makes a nice combination for a uBITX. The only thing I lack is the firmware. We have use those OLEDs in a couple of devices and (if they don't generate too much interference) look very nice and super sharp....FWD, REV, VSWR, ? Could also drive it with one of the many signal generators out there to allow a low level antenna "Tune" function for the attached Transceiver. 

We also have a LED bargraph version which requires NO firmware ....but it's only $2-3 less and lacks being as user friendly. You guys who write the firmware control the road.

73 Kees K5BCQ

Re: Oscilloscope on sale

Jerry Gaffke
 

I think that upgrade trick was mostly for the $400 Rigol DS1052E 50mhz scope.
Rigol was selling a 100mhz scope for extra bucks that was identical except for the firmware,
strictly a marketing decision.

Now that there are scopes under $300 with a bandwidth of 200mhz (assuming they work),
the gloves are off, I'd guess they're all going for max bandwidth for minimum cost.
And if somebody is crippling their hardware, they likely make it harder to upgrade
on the cheap having seen what happened with the Rigol. 

Jerry, KE7ER



On Fri, Jun 22, 2018 at 08:52 am, Ralph Mowery wrote:
I have seen on youtube where some have flashed the software in some of the scopes and other devices to raise them up to higher levels.  There may or may not be some small components in them that limit the bandwidth so you may not be able to get the traces to show a true waveform at the higher frequency.
 
 

Re: W8TEE Power/SWR Sketch for Nano

Jack, W8TEE
 

Kees:

It appears that a good part of the code was taken from the Adafruit library examples:




On Friday, June 22, 2018, 12:54:39 PM EDT, Jack Purdum via Groups.Io <jjpurdum@...> wrote:


I do have code for the 0.96" OLED's, as that's what we used for the DL I've mentioned before. Do you need it?

Jack, W8TEE

On Friday, June 22, 2018, 12:52:17 PM EDT, Kees T <windy10605@...> wrote:


Jack,

Don't you have an Arduino sketch for a Nano which uses AD8307s for input and outputs to a 16x2 screen or one of the 1" OLED displays via I2C ?

73 Kees K5BCQ   

Re: Understanding Spurious Emissions

Jerry Gaffke
 

I wouldn't operate the transmitter on 15m,12m,10m without
either a fix for the spur or some way to monitor it.

Monitoring could be done with a second receiver plus a step attenuator.
Transmit into a dummy load while monitoring the spur at 44.995mhz-Fop through a step attenuator, 
where Fop is your operating frequency.
So if you are operating at  Fop = 29.0 mhz, the spur is at 44.995-29=15.995mhz, give or take a couple khz. 
Determine the signal strength of the spur, perhaps using the receiver S-meter.
Then tune in your operating frequency, and use the step attenuator to reduce the strength of your main signal
into the dummy load until you get the same S-meter reading as you did for the spur.
The additional attenuation required tells you how many dB below your main signal that spur is.
A good source for a step attenuator is the "Attenuator Kit #13" from Kees:  http://www.qsl.net/k5bcq/Kits/Kits.html

If you can't be bothered to do the procedure above, it may not be a good idea to be transmitting 
on the 15m, 12m and 10m bands using the uBitx.
This is especially true if you have jacked up your mike gain somehow to get more power out,
or are running your uBitx into a high powered external amplifier.

Some do report that a properly adjusted uBitx can have that spur down near the legal limit
of 43 dB below the main signal.  But that is pretty much the best possible case.
Your best possible case could be much worse, the gain of the 45mhz amp in particular will be
all over the map depending on the characteristics of the mmbt3904's that happen to be in your rig.
And it will definitely get worse if you raise the mike gain, or shout into the mike.
We seem to know the best case, I would want to know my worst case 
before attempting to operate on these upper bands. 


There are several solutions to this.

We could call it a rig suitable for operation from 160m to 17m, forget the upper bands,
replacing the top transmit LPF with one suitable for 160m.

We could replace the 30mhz LPF at L1,2,3,4 with different filters for each band.
This is what pretty much all other HF transceivers do.

Or we could raise the first IF frequency from 45mhz to something well above 60mhz,
perhaps the 86.85mhz of post   https://groups.io/g/BITX20/message/52460
Since 86.85mhz - 30mhz puts the lowest possible frequency for the spur at 56.85mhz,
the spur won't get through the stock 30mhz LPF at L1,2,3,4


I'd prefer to see a fix that replaces the 45mhz IF, everything there including those two diode ring mixers.
This could be a small daughterboard that mounts into the holes remaining when the mixer transformers are removed.
All 6 mmbt3904's would be replaced with BFR106's, the 86.85 mhz PX1002 is used as the filter,
the mixers redesigned for 86mhz.  Gains would be adjusted in both IF amps to minimize the spurs,
and also minimize the carrier we have leaking through.
Parts count and topology remain the same as the stock uBitx, no added complexity,
though we could add some sort of RF AGC attenuator for some extra pennies.
The better transistors will allow an even drive to the PA, giving us a better shot at getting
the same power out to the antenna on 10m as on 80m.
Total cost of parts can be under $10, so it might be a kit that sells for $20 at sufficient volume.
If hfsignals decides to move in this direction, the only significant hit on cost or procurement
would be the $6 PX1002 (volume pricing) vs the custom built 45mhz crystal filter (whatever that costs).
This has not yet been tried.

Jerry, KE7ER


On Fri, Jun 22, 2018 at 05:18 am, ajparent1/KB1GMX wrote:
No, your analogy would be right if you were on the wrong side of the road. 
If you get near even fully driving the modulator the last mixer is easily 10+ db
past saturated as result of there being enough IF gain to assure that.

For those that never go above 20Mhz its adequately filtered and not an issue.

Allison
#############
Howard Fidel  June 21   #52728

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.