Date   
Re: Need 12.000 MHz crystals for the BITX40 #bitx40help #bitx40

Jerry Gaffke
 

Here's a nice classic article on crystal ladder filters:
    https://www.arrl.org/files/file/QEX_Next_Issue/Nov-Dec_2009/QEX_Nov-Dec_09_Feature.pdf
Lots of other stuff out on the web describing other aspects of this.
Also in EMRFD.

They recommend that crystals be matched in frequency to within +-2% of your filter bandwidth.
So for a 2500hz SSB bandwidth, the crystals should be within +-50hz.
If you buy well spec'd crystals from a reputable distributor,
they might be held to within 20ppm, or within 12mhz*20ppm = +-240 hz.
You will need quite a few of them sorted by frequency
to get a bunch within 50hz of some center frequency.

I don't know what's in that bag of cheap crystals.
Perhaps they are a surplus run of really good 20ppm crystals.
Perhaps they were rejected because they were well beyond 100ppm off frequency.
Perhaps they were not active enough, and would thus make for a very lossy filter.

Mouser and Digikey sell 10ppm crystals of known provenance at 2 for the dollar,
20ppm and 50ppm for quite a bit cheaper.

It's not just frequency that should be matched, though that's the most important.
Read the article.
Though if not too worried about passband shape and loss, and with some luck,
you can just try some crystals matched in frequency and see what you get.
It may be necessary to try different cap values and termination impedances
till the filter works well enough.

Or you may find out it's best to simply go through the steps outlined in the article..

Jerry


On Tue, Oct 23, 2018 at 08:00 AM, Bill Cromwell wrote:
I am thinking that your 50 percent is on the low side and of the other 50 percent many of those would match well enough as an additional set of filters.

Re: Wiring of power plug #bitx40

Gary Anderson
 

RG,

Let’s see if I can walk you through this.  Let’s call the piece you mount on the uBITX chassis the ‘socket’ and the piece you supply power from the ‘plug’.  The plug has 2 solder connection tabs.  The socket has 3 solder connection tabs.   Plug the plug into the socket and get out your ohm meter/ continuity tester.

Find the 2 tabs on the socket that have continuity to the corresponding 2 tabs to the plug.  The third tab on the socket will not have continuity to the plug.  This is all you need for uBITX wireup.


If you remove the plug, you will find that 2 tabs on the socket have continuity.
This style of socket is often used to switch the power source from an internal battery to an external source.

 

As far as which tabs you select for +12V and ground, it’s up to you as there is no universal standard. I strongly prefer and recommend the +12V on the inside connection of the plug, as to lessen the chance of a short when the plug is powered and not in the socket.  Most, but not all, are wired this way.

If you are still stuck after this, I can take some pictures to help out when get home.

Regards,

Gary

Re: One Month With The uBitx

Bill Cromwell
 

Hi Curt,

We don't need the "QRP card". Our license is as good as anybody else. In 1981 I took a Ten Tec Argonaut 509 (2 watts wide open) to Field day and used it as our 80 meter station on CW. It held it's own against the 100 watt stations :) A new novice licensee was put with me for logging and duping (no computers then). As the hours wore on he became quite proficient at CW as it is used in contest exchanges. By 2AM he was at the key and I was logging and duping :) 10 watts is 5 times the power of that 509 and a couple of s-units higher on distant receivers. Just act as if you belong on the bands, You do.

73,

Bill KU8H

On 10/23/2018 10:06 AM, Curt M. wrote:
Hi guys, last month I finished up the build on my uBitx. It's
completely stock other than using some outboard filters. I decided to
humor myself and for one month exclusively use only the uBitx. I have
to say that I'm impressed with the results.

With just casually making contacts I made 61 between 40, 20 & 80m.
Those contacts were in 18 states plus Slovenia and Belgium. Being that
the last month has had a state QSO party or two every weekend that kind
of increased the contact to state ratio but it gave me a lot of
opportunities to make some contacts when I could fit it in. At no point
did I sit down and spent more than 15 minutes trying to make contacts.
I think had I sat through a QSO party or two for an extended period of
time I could have done even better. Also I did not make one contact by
throwing out the QRP card, that made it even more of a challange. I had
a few contacts that I struggled with along the way but there were five
times more immediately successful contacts than ones that I struggled with.

During this last month I also checked into a bunch of nets. When
checking into one net during their 73 round the net control operator
asked me where I was located and what I was running becuase he said the
band was in such bad shape that day that they didn't have as many
check-in's. He seemed to be impressed with how I was making it into his
location on about 8 watts. He closed down the net and all of the sudden
people started throwing out my call sign to make contact with me. I
picked up about 4 new states in a few minutes that said I was making it
into them with varying degrees of signal strength. One guy said that I
was about an S5 but I was 10 over at one point while talking to another
guy before him. So that was a lot of fun.

So my take-away from this last month is that if the uBitx was your only
radio, even though it doesn't have fancy filters and all of the other
stuff like a mainstream radio does, you can still have a lot of fun and
make contacts. I will say that I missed having AGC and although the pop
when you key up is annoying, it's bearable. Both can be fixed through
various mods.

Last night I turned on my IC-7300 for the first time in a month and even
though it's a great radio in it's class, making contacts with less power
and not telling anyone what you are running unless they ask is really a
lot of fun. I see me getting use out of both radios but I was amazed at
how well the uBitx performed at less than one tenth the power.

73

Curt M.
--
bark less - wag more

Re: Simple spur fix

 

At 23-10-18, you wrote:
Hi Joe,

I am not sure what you used to replace L5 and L7. I tried

Coilcraft air coil - terrible spurs worse than stock.
Shielded Coilcraft - much better and almost same as the stock
1206 size ferrite one - big loss of signal and power
1210 yellow one marked S+M - slight loss of signal and power (about 0.5W on 40)

1210 gave the best reduction in spurs, Axicom relays for KT1,2,3 help a lot more additionally and gets rid of
lower band harmonics.

Assorted
https://www.ebay.com/itm/142968653807

Mine looks like this
https://www.ebay.com/itm/142968653807

I have ordered the assorted to check if it works the same as my China assorted pack.

Send me a pic of what you put to vu2zap @ gmail.com and let me see what they are!
or whats app to number below.

Raj
+919483843939


At 23-10-18, you wrote:
>Hi Raj, I Replaced L5 and L7 and by observing my waterfall on the panadapter I installed and comparing it to my commercial rig it seems like the receiver is not as sensitive as before. Even the circuit Im feeding for A7 for signal streghtn is not hitting as expected on strong signal. Its a !ittle weaker then before.
>
>I bascially took the 45mhz 2nd filter that I added back out put a through hole 47ohm back in its place. I didnt have smd. Is also dont have any good test equipment so I cant tell you much but I was wondering, Raj if you noticing a slight loss in receive with the mod?
>
>Joe

Re: One Month With The uBitx

Curt M.
 

Hi Dave, after using my uBitx for one day I did install the CEC firmware which I forgot to mention.  That makes it's really easy to use and experiment with being that you can backup and restore your settings.

As far as kits go I started out with a Bitx40 in which right out of the gate I received a non functional board.  I was never able to figure out what was wrong with it.  The replacement board came, I didn't change a thing with my wiring and just connected the board up and it's been fully functional from the get go.

I'm hoping that these kits will spin off some kids that are getting their feet wet in electronics with Raspberry Pi's and maybe we'll get a new crop of hams.

Re: Simple spur fix

 

Sorry for repeated link. This is the one.

https://www.ebay.com/itm/141772698395

At 23-10-18, you wrote:

Mine looks like this
https://www.ebay.com/itm/142968653807

Re: One Month With The uBitx

Curt M.
 

Thanks Jack!  The uBitx is definitely a sleeper product.  All of us on here know about it but there are so many people that do not.  I made a quick sort of a raw video of my uBitx and sent it to some local hams.  A few of them immediately ordered one.  I'm sure they will have a lot of fun with it also.    

I just built up one of the QRSS WSPR 6 band kit from QRP-Labs.  That's a fairly time consuming kit if you are going to build all of the filters but the reward is very much worth it.  I have a 40m QCX on the way which I hope will entice me to get a little more proficient with CW.  In the next week I have the 10W linear amp for the QSX coming so I can get that part built while Hans finishes up the things that he needs to on the QSX.  Luckily he's going to make it an option to buy the QSX without the amp so anyone that wants to get a jump on building that kit can order the amp now and the rest later.  I really feel like the QSX is going to be the first game changer of many to come in the modern day world of kit radios.

Curt

Re: One Month With The uBitx

Dave Dixon
 

Hi CURT,
              Congratulations,ive been running a couple of bitx radios for a while now,1 is version 3 and the others version 4. and like you am amazed at the results im getting,the only changes ive made are adding KD 8 CEC firmware on both and a blue lcd screen on 1 and a touch colour screen on the other.I sold my,k3 and k2 and am totally home brew now save a power supply,.So far ive worked 60 countries on 40 mtrs.and most days conditions prevailing into europe nothng spectacular, but pleased to take what comes out of the speaker ive only wire aerials here plus i live in an area of conservation.Dave G0 AYD QRZ.COM

And all thanks to Ashar Farnham..

also to Jack W8 TEE whose sentiments i totally agree with.
i keep talking to the newly licenced guys on 2 mtrs over here and tell them about the ubitx.


On Tue, 23 Oct 2018 at 15:06, Curt M. <Kc3hjp@...> wrote:
Hi guys, last month I finished up the build on my uBitx.  It's completely stock other than using some outboard filters.  I decided to humor myself and for one month exclusively use only the uBitx.  I have to say that I'm impressed with the results.

With just casually making contacts I made 61 between 40, 20 & 80m.  Those contacts were in 18 states plus Slovenia and Belgium.  Being that the last month has had a state QSO party or two every weekend that kind of increased the contact to state ratio but it gave me a lot of opportunities to make some contacts when I could fit it in.  At no point did I sit down and spent more than 15 minutes trying to make contacts.  I think had I sat through a QSO party or two for an extended period of time I could have done even better.  Also I did not make one contact by throwing out the QRP card, that made it even more of a challange.  I had a few contacts that I struggled with along the way but there were five times more immediately successful contacts than ones that I struggled with.

During this last month I also checked into a bunch of nets.  When checking into one net during their 73 round the net control operator asked me where I was located and what I was running becuase he said the band was in such bad shape that day that they didn't have as many check-in's.  He seemed to be impressed with how I was making it into his location on about 8 watts.  He closed down the net and all of the sudden people started throwing out my call sign to make contact with me.  I picked up about 4 new states in a few minutes that said I was making it into them with varying degrees of signal strength.  One guy said that I was about an S5 but I was 10 over at one point while talking to another guy before him.  So that was a lot of fun.

So my take-away from this last month is that if the uBitx was your only radio, even though it doesn't have fancy filters and all of the other stuff like a mainstream radio does, you can still have a lot of fun and make contacts.  I will say that I missed having AGC and although the pop when you key up is annoying, it's bearable.  Both can be fixed through various mods.

Last night I turned on my IC-7300 for the first time in a month and even though it's a great radio in it's class, making contacts with less power and not telling anyone what you are running unless they ask is really a lot of fun.  I see me getting use out of both radios but I was amazed at how well the uBitx performed at less than one tenth the power.

73

Curt M.

Re: Need 12.000 MHz crystals for the BITX40 #bitx40help #bitx40

Bill Cromwell
 

Hi Steve,

My own idea was that if they are all off a bit and all off the same amount they're *good*. Each uBitx has to be tweaked a little because the filters and the clock xtals are all just a little different one from another. My experience with xtal filters in older ham gear points to the same thing. None of them would be at 9.00000000000000000000000000000000000 or 12.000000000000000000000000 MHz.

I am thinking that your 50 percent is on the low side and of the other 50 percent many of those would match well enough as an additional set of filters.

73,

Bill KU8H

On 10/23/2018 10:48 AM, G1KQH via Groups.Io wrote:


I am sure out of 100 you could get 50% of them to match and maybe more!


73 Steve
--
bark less - wag more

Re: Need 12.000 MHz crystals for the BITX40 #bitx40help #bitx40

G1KQH
 



I am sure out of 100 you could get 50% of them to match and maybe more!


73 Steve

Re: Simple spur fix

iz oos
 

Yes, for low sensitivity check all these resistors around the 6 2N3904 used for receive from the first to the second IF filters. If a resistor is fried, the signal will pass anyway through the transistor but attenuated instead of being amplified. If you have an issue on both transmit and receive then it is likely something shared by both the and rx, like the IF filters (and of course the coils you replaced). So maybe just replacing them you might have full sensitivity back


Il 23/ott/2018 16:26, "Joe Puma" <kd2nfc@...> ha scritto:
Iz, I remember you mentioning a weak receive, I was trying to find your emails to compare if I had the same issue, I will check R36. 

Joe



On Oct 23, 2018, at 3:55 AM, iz oos <and2oosiz2@...> wrote:

Joe, let's see what Raj think about it. In my view if you have replaced L5 and L7 and you observe about the same TX output then replacing them can't harm the receiver. I would check the resistors on the 2N3904 chain if they have a correct value. When I tried the IF output I did fry R36 and I have no clue how I did it except for that I used a 25w iron for a very short time.


Il 23/ott/2018 08:14, "Joe Puma" <kd2nfc@...> ha scritto:
Hi Raj, I Replaced L5 and L7 and by observing my waterfall on the panadapter I installed and comparing it to my commercial rig it seems like the receiver is not as sensitive as before. Even the circuit I’m feeding for A7 for signal streghtn is not hitting as expected on strong signal. It’s a !ittle weaker then before. 

I bascially took the 45mhz 2nd filter that I added back out put a through hole 47ohm back in its place. I didn’t have smd. Is also don’t have any good test equipment so I can’t tell you much but I was wondering, Raj if you noticing a slight loss in receive with the mod?

Joe





Re: Simple spur fix

Joe Puma
 

Iz, I remember you mentioning a weak receive, I was trying to find your emails to compare if I had the same issue, I will check R36. 

Joe



On Oct 23, 2018, at 3:55 AM, iz oos <and2oosiz2@...> wrote:

Joe, let's see what Raj think about it. In my view if you have replaced L5 and L7 and you observe about the same TX output then replacing them can't harm the receiver. I would check the resistors on the 2N3904 chain if they have a correct value. When I tried the IF output I did fry R36 and I have no clue how I did it except for that I used a 25w iron for a very short time.


Il 23/ott/2018 08:14, "Joe Puma" <kd2nfc@...> ha scritto:
Hi Raj, I Replaced L5 and L7 and by observing my waterfall on the panadapter I installed and comparing it to my commercial rig it seems like the receiver is not as sensitive as before. Even the circuit I’m feeding for A7 for signal streghtn is not hitting as expected on strong signal. It’s a !ittle weaker then before. 

I bascially took the 45mhz 2nd filter that I added back out put a through hole 47ohm back in its place. I didn’t have smd. Is also don’t have any good test equipment so I can’t tell you much but I was wondering, Raj if you noticing a slight loss in receive with the mod?

Joe




Re: Wiring of power plug #bitx40

Ruarto <rhgalyan@...>
 

Thanks.   Not sure yet how,when I will use it (General ticket) but Im legal when I do.   I wanted to do this as a kid,  I was a novice at 12 in 1954.  

 

Im having troubles with shakes and such so this ubitx was probably not a good choice.  Plus Im not a programmer,  or a electronics whiz like so many of you guys on these lists are.   But Im going to keep on trying to get it together.

 

So far the ubitx.net doesn’t seem to address the power plug issue,  but I will keep looking.

 

Thanks again for the reply.

 

RG

 

Sent from Mail for Windows 10

 

From: w4rjp
Sent: Tuesday, October 23, 2018 7:59 AM
To: BITX20@groups.io
Subject: Re: [BITX20] Wiring of power plug #bitx40

 

Robin:   Mike's ubitx.net, ubitx Wiki, and the files section of this group have help in wiring up the DC power jack.   HF Signals also has help.  I would start with ubitx.net. Mike's site is outstanding!

By the way congratulations on passing your General class license.

Bob, W4RJP

 

Re: Simple spur fix

Joe Puma
 

Thanks guys and good morning from New York. This is the part I ordered from Mouser. 

MFG Part No: DFE322512F-R68M=P2 Murata Electronics 1210 0.68uH 20% / Fixed Inductors


I currently can’t check output power because I don’t have a power meter and never took a baseline test before the mod. I can only gauge by the receive being weaker than before. I suppose I can do a current draw test with my DMM but I don’t have a baseline test with the original coils in. 

Looks like I'll grab the assorted kit Raj posted. This should probably be added to the ubitx.net where I was following the instructions of the mod. 


Joe



On Oct 23, 2018, at 3:55 AM, iz oos <and2oosiz2@...> wrote:

Joe, let's see what Raj think about it. In my view if you have replaced L5 and L7 and you observe about the same TX output then replacing them can't harm the receiver. I would check the resistors on the 2N3904 chain if they have a correct value. When I tried the IF output I did fry R36 and I have no clue how I did it except for that I used a 25w iron for a very short time. 


Il 23/ott/2018 08:14, "Joe Puma" <kd2nfc@...> ha scritto:
Hi Raj, I Replaced L5 and L7 and by observing my waterfall on the panadapter I installed and comparing it to my commercial rig it seems like the receiver is not as sensitive as before. Even the circuit I’m feeding for A7 for signal streghtn is not hitting as expected on strong signal. It’s a !ittle weaker then before. 

I bascially took the 45mhz 2nd filter that I added back out put a through hole 47ohm back in its place. I didn’t have smd. Is also don’t have any good test equipment so I can’t tell you much but I was wondering, Raj if you noticing a slight loss in receive with the mod?

Joe




Re: One Month With The uBitx

Jack, W8TEE
 

Curt:

Thanks for telling us about this. I'm always selling the µBITX to whomever will listen, but not because it's QRP, but because it can bring into the fold new operators who may have a misconception about our hobby. I've told this story before, but it's worth repeating. My club (Milford Amateur Radio Club) always had a GOTO station and in 2015, we had a 13 year old who made contacts almost from coast-to-coast. I was listening to him excitedly telling his mother what he had just done--he could hardly contain himself he was so excited! His mother looked at him and said: "It sounds like a wonderful hobby, but where are you going to get the thousands of dollars it takes to buy the radio?" He looked like he had just been shot...

Ever since that day, I've been doing what I can to promote low-cost HF operation, especially to people starting out on a lawn-mowing budget. The µBITX, QCX, Forty-9er, up-coming QSX, and many others all work towards that goal.

Share your story on the air. You never know: Somebody may be listening who is speaking at a Cub Scout or GIrl Scout meeting is a few days and he may point out that you can buy a viable rig for a reasonable sum of money.

Good work!!

Jack, W8TEE


On Tuesday, October 23, 2018, 10:06:40 AM EDT, Curt M. <Kc3hjp@...> wrote:


Hi guys, last month I finished up the build on my uBitx.  It's completely stock other than using some outboard filters.  I decided to humor myself and for one month exclusively use only the uBitx.  I have to say that I'm impressed with the results.

With just casually making contacts I made 61 between 40, 20 & 80m.  Those contacts were in 18 states plus Slovenia and Belgium.  Being that the last month has had a state QSO party or two every weekend that kind of increased the contact to state ratio but it gave me a lot of opportunities to make some contacts when I could fit it in.  At no point did I sit down and spent more than 15 minutes trying to make contacts.  I think had I sat through a QSO party or two for an extended period of time I could have done even better.  Also I did not make one contact by throwing out the QRP card, that made it even more of a challange.  I had a few contacts that I struggled with along the way but there were five times more immediately successful contacts than ones that I struggled with.

During this last month I also checked into a bunch of nets.  When checking into one net during their 73 round the net control operator asked me where I was located and what I was running becuase he said the band was in such bad shape that day that they didn't have as many check-in's.  He seemed to be impressed with how I was making it into his location on about 8 watts.  He closed down the net and all of the sudden people started throwing out my call sign to make contact with me.  I picked up about 4 new states in a few minutes that said I was making it into them with varying degrees of signal strength.  One guy said that I was about an S5 but I was 10 over at one point while talking to another guy before him.  So that was a lot of fun.

So my take-away from this last month is that if the uBitx was your only radio, even though it doesn't have fancy filters and all of the other stuff like a mainstream radio does, you can still have a lot of fun and make contacts.  I will say that I missed having AGC and although the pop when you key up is annoying, it's bearable.  Both can be fixed through various mods.

Last night I turned on my IC-7300 for the first time in a month and even though it's a great radio in it's class, making contacts with less power and not telling anyone what you are running unless they ask is really a lot of fun.  I see me getting use out of both radios but I was amazed at how well the uBitx performed at less than one tenth the power.

73

Curt M.

One Month With The uBitx

Curt M.
 

Hi guys, last month I finished up the build on my uBitx.  It's completely stock other than using some outboard filters.  I decided to humor myself and for one month exclusively use only the uBitx.  I have to say that I'm impressed with the results.

With just casually making contacts I made 61 between 40, 20 & 80m.  Those contacts were in 18 states plus Slovenia and Belgium.  Being that the last month has had a state QSO party or two every weekend that kind of increased the contact to state ratio but it gave me a lot of opportunities to make some contacts when I could fit it in.  At no point did I sit down and spent more than 15 minutes trying to make contacts.  I think had I sat through a QSO party or two for an extended period of time I could have done even better.  Also I did not make one contact by throwing out the QRP card, that made it even more of a challange.  I had a few contacts that I struggled with along the way but there were five times more immediately successful contacts than ones that I struggled with.

During this last month I also checked into a bunch of nets.  When checking into one net during their 73 round the net control operator asked me where I was located and what I was running becuase he said the band was in such bad shape that day that they didn't have as many check-in's.  He seemed to be impressed with how I was making it into his location on about 8 watts.  He closed down the net and all of the sudden people started throwing out my call sign to make contact with me.  I picked up about 4 new states in a few minutes that said I was making it into them with varying degrees of signal strength.  One guy said that I was about an S5 but I was 10 over at one point while talking to another guy before him.  So that was a lot of fun.

So my take-away from this last month is that if the uBitx was your only radio, even though it doesn't have fancy filters and all of the other stuff like a mainstream radio does, you can still have a lot of fun and make contacts.  I will say that I missed having AGC and although the pop when you key up is annoying, it's bearable.  Both can be fixed through various mods.

Last night I turned on my IC-7300 for the first time in a month and even though it's a great radio in it's class, making contacts with less power and not telling anyone what you are running unless they ask is really a lot of fun.  I see me getting use out of both radios but I was amazed at how well the uBitx performed at less than one tenth the power.

73

Curt M.

Re: UBitx purchase without Raduino

Dennis Yancey
 

I have a couple of extra Raduino’s .. just like to get the main board.
--
72 and God bless
KD4EPG

Re: Wiring of power plug #bitx40

w4rjp
 

Robin:   Mike's ubitx.net, ubitx Wiki, and the files section of this group have help in wiring up the DC power jack.   HF Signals also has help.  I would start with ubitx.net. Mike's site is outstanding!

By the way congratulations on passing your General class license.

Bob, W4RJP

PA Alignment of uBITX #ubitx

John Groezinger
 

Hi All, 
I have completed assembly of uBITX and generally things seem to be working.
I decided to do uBITX 3 step alignment starting with PA bias.
Roughly, instructions say turn pots all the way down, observe current, and add 100mA (x2) with each pot.
I ended up with a minimum of 400mA for starting point (not 470-500mA per instructions) and an adjusted current of 600mA after complete.
Does this agree with other people's observations?
John N9COQ

uBITX doing well on 60 meters

Bill Meara