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Re: How to get 5W on 10m?

 

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Iz Oos

Using LTSpice is not all that difficult (I learned it and I'm not that brilliant).

There are two parts to learn.? First is the schematic editor that is intuitive once you know some basic select-and-place moves.? After you have the schematic complete you would select voltage sources and measuring points.? The rest is mostly automatic when you select "RUN" mode.

Start with a small circuit segment to get a feel for how it works and then build on that experience.? In a few hours you will be an expert.

LTSpice is FREE and will run on Windows or any version of Linux with Wine installed.??

Arv
_-_


Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: iz oos <and2oosiz2@...>
Date: 3/9/19 12:04 AM (GMT-07:00)
Subject: Re: [BITX20] How to get 5W on 10m?

What about adding a capacitor (like a 180pf or maybe a higher value) in parallel with r83? Would it increase the 10m power output without decreasing the output in the other bands (I wish I knew how to use LTspice)?


Il 02/mar/2019 11:47, "iz oos via Groups.Io" <and2oosiz2=[email protected]> ha scritto:

I replaced the cap at the emitter of Q90 with a 470pf instead of the 0.1nF. In the meanwhile I replaced the bifilar antenna wire with a short coax. Output power on 40 marginally diminished from 15 to 12.5w about. The power on higher bands marginally increased from nearly 2w to nearly 2.5w. But the 'instability' issue with full throttle noise on SSB on 10m has disappeared and I can also not attenuate the Vogad output. Overall I am happy with this one component replacement.


Il 01/mar/2019 08:40, "iz oos via Groups.Io" <and2oosiz2=gmail.com@groups.io> ha scritto:

Thanks for all the replies. According to the old schematics of my ver. 3 ubitx C81 should be 0.1nF, so I will see what changes with a 470pf as suggested by Farhan.


Il 28/feb/2019 23:58, "ajparent1/KB1GMX" <kb1gmx@...> ha scritto:
BITX V5 as distriibuted.? I believe its part of the Zip file on github.
Here is a copy attached.

As far as power amp there were no changes and is the same for emitter cap (c81) on Q90
going back to V3.

Allison

Gigaparts selling ubitx!!!

Kelly Mabry
 

开云体育

Haven't confirmed the version yet...

K5AID?



Sent from my Verizon, Samsung Galaxy smartphone
Re: The Iambic Mouse

 

izooz
Looks like we are approaching from opposite sides. I might try it with the unused 5 pin mike port.
Dave
Re: BFR93W

 

The item i get is bfr93a that has upper limit of 12V
?BFR93w as made by Siemens has 15V and is in sot323 package , perhaps close to sot23 we an solder.
Please search for it.


On Sat, Mar 9, 2019 at 3:33 PM MVS Sarma via Groups.Io <mvssarma=[email protected]> wrote:
?I had ordered on this seller

?but please see the datasheet.BFR93a? supply is 12V
?Hence we should not try 13.8 , little extra . No
regards
sarma
vu3zmv

On Sat, Mar 9, 2019 at 12:41 PM Lawrence Galea <9h1avlaw@...> wrote:
Does anyone know of a decent supplier for the BFR93W?
Or is it possible for hfsignals to make them available to those who purchased the μbitx?
Regards
Lawrence
Re: BFR93W

 

?I had ordered on this seller

?but please see the datasheet.BFR93a? supply is 12V
?Hence we should not try 13.8 , little extra . No
regards
sarma
vu3zmv


On Sat, Mar 9, 2019 at 12:41 PM Lawrence Galea <9h1avlaw@...> wrote:
Does anyone know of a decent supplier for the BFR93W?
Or is it possible for hfsignals to make them available to those who purchased the μbitx?
Regards
Lawrence
Re: BFR93W

 

BFR93A


Il 09/mar/2019 09:35, "iz oos" <and2oosiz2@...> ha scritto:

The main issues are two: 1) buying in small quantities; 2) low shipping rates. For instance, sells very reliable components but requires you buy a total amount of at least 30�. Btw, they have BRF93A, not sure if they are the same thing.


Il 09/mar/2019 08:49, "Curt via Groups.Io" <wb8yyy=[email protected]> ha scritto:
I am thinking that most v4 and v5 rigs do not need them. It may depend which spur mod you do for an added 45 MHz filter. I am getting around 4 watts on 28 MHz cw with stock transistors and an added LC filter only in transmit path. I don't imagine its a huge difference on receive. I am also thinking that other vhf npn devices could be found in junk.

Curt

Re: BFR93W

 

The main issues are two: 1) buying in small quantities; 2) low shipping rates. For instance, sells very reliable components but requires you buy a total amount of at least 30�. Btw, they have BRF93A, not sure if they are the same thing.


Il 09/mar/2019 08:49, "Curt via Groups.Io" <wb8yyy=[email protected]> ha scritto:
I am thinking that most v4 and v5 rigs do not need them. It may depend which spur mod you do for an added 45 MHz filter. I am getting around 4 watts on 28 MHz cw with stock transistors and an added LC filter only in transmit path. I don't imagine its a huge difference on receive. I am also thinking that other vhf npn devices could be found in junk.

Curt

Re: BFR93W

 

I am thinking that most v4 and v5 rigs do not need them. It may depend which spur mod you do for an added 45 MHz filter. I am getting around 4 watts on 28 MHz cw with stock transistors and an added LC filter only in transmit path. I don't imagine its a huge difference on receive. I am also thinking that other vhf npn devices could be found in junk.

Curt
BFR93W

 

Does anyone know of a decent supplier for the BFR93W?
Or is it possible for hfsignals to make them available to those who purchased the μbitx?
Regards
Lawrence
Re: How to get 5W on 10m?

 

What about adding a capacitor (like a 180pf or maybe a higher value) in parallel with r83? Would it increase the 10m power output without decreasing the output in the other bands (I wish I knew how to use LTspice)?


Il 02/mar/2019 11:47, "iz oos via Groups.Io" <and2oosiz2=[email protected]> ha scritto:

I replaced the cap at the emitter of Q90 with a 470pf instead of the 0.1nF. In the meanwhile I replaced the bifilar antenna wire with a short coax. Output power on 40 marginally diminished from 15 to 12.5w about. The power on higher bands marginally increased from nearly 2w to nearly 2.5w. But the 'instability' issue with full throttle noise on SSB on 10m has disappeared and I can also not attenuate the Vogad output. Overall I am happy with this one component replacement.


Il 01/mar/2019 08:40, "iz oos via Groups.Io" <and2oosiz2=gmail.com@groups.io> ha scritto:

Thanks for all the replies. According to the old schematics of my ver. 3 ubitx C81 should be 0.1nF, so I will see what changes with a 470pf as suggested by Farhan.


Il 28/feb/2019 23:58, "ajparent1/KB1GMX" <kb1gmx@...> ha scritto:
BITX V5 as distriibuted.? I believe its part of the Zip file on github.
Here is a copy attached.

As far as power amp there were no changes and is the same for emitter cap (c81) on Q90
going back to V3.

Allison

Re: uBitx V4 Audio extremely quiet and other needed mods#ubitx

 

Raj, I hope this is a joke and not a real true...? :/


Il 07/mar/2019 14:10, "Raj vu2zap" <rajendrakumargg@...> ha scritto:
Today they have the technology to put in the magic smoke even in the smallest components.
Nobody can stop the release of the smoke, not even me.

Amazing!

Raj, vu2zap

At 07-03-19, you wrote:
Come on now.... that is half the fun of ham radio.... doing something you don’t have a clue about just to see if it works.? It’s like going to the casino and hoping it’s your lucky day.? Ha!? When the smoke comes out you learn an unforgettable lesson.

David J. Wilcox K8WPE’s iPad

On Mar 6, 2019, at 9:52 PM, Wayne Leake <wayneleake@...> wrote:

?The mention of not plugging or unplugging the headphone/speaker with the radio on reminded me of an incident years ago.
?I did radio repairs in my brothrs TV hop yers ago.
?Had a customer brought in a Bearcat IV scanner with no audio.
?seems he decided to install an RCA jack on the back to plug an external speaker in.
?However, he did so with the radio plugged in and "ON"
?Cost him a few $$ to replace the audio IC.
?A bit of a costly lesson for him.

?Always work on things with the radio off, and even unplugged, except for making tests when you know what you are doing.
?Wayne WA2YNE
Re: Should I wait to buy a ubitx?

 

I wouldn't wait for a ver 6. Although I would have liked to read an independent and thorough SA analysis by users or a QST review with the ARRL measurements. Version 3 was deeply analyzed. Criticisms by Allison (SSB spurs above 17m) and Warren/Allison (unsufficient harmonics suppression) seems tackled in this version 5. The low audio issue typical of version 4 also seems solved for good.


Il 09/mar/2019 05:36, "Jack Purdum via Groups.Io" <jjpurdum=[email protected]> ha scritto:
Something else to consider: Al and I have build a number of ?BITX's as have members of our Builders Group. All of them that we know about are within spec on 80M and 40M. All were also on spec on 20M, but 2 were "on spec", but close enough that it might be within or outside of spec on a lab SA. Both of those, however, were within 1.96σ.

So, if you only have an antenna for 80 and 40 meters, it's likely a moot question. If you plan to work 20M and below, I'd say buy it and see if it's in spec or not. If not, chances are you can sell it on this Forum for close to what you paid for it.

I'd hate to see you pass up the enjoyment this little rig can afford you. You're going in with your eyes open and if it doesn't make you happy, you have a plan for recouping the lion's share of your cost. What the heck...Custer took a chance...

My $0.02 are in the ring...stepping down from soapbox...

Jack, W8TEE

On Friday, March 8, 2019, 11:02:57 PM EST, Brutus Laurentius <markhamfarm14@...> wrote:


We all have our biases, which include maybe a bit of projection ... and I'm projecting that this is a fun kit well worth buying.

Now, in saying that, I am pretty handy with a soldering iron and hot air too, along with magnified goggles and good lighting.??

Like anything this fun, there are a lot of ways to approach it.? But the thing is, this radio is very hackable.??

I believe, especially if you adjust Rv1 for 5 watts and do the other calibration required, you won't be getting cited by the FCC.

My experience is with a V4 with all the "fixes" plus I? incorporated most of the changes (except for the IF frequency change) from the V5, as well as replacing the driver transistors, etc.? I ultimately put the filters on a little daughter card on top of the originals.? Next I'll be adding agc.

I happen to have access to a spectrum analyzer at work, and with that done, as long as I kept the output below 7.5 w on my band of choice, I had nothing that was a problem.? ?

A bit of patience, tweaking and fun, and at least for me, the rig has turned out usable!
Re: Which version of the ubitx board is currently shipping?

 

Yes it is Ver.5


On Sat, 9 Mar 2019, 9:58 am Kelly Mabry <kmabry2007@... wrote:

Just to ask, is the V5 board shipping as of today? Sorry for the question? here, I did not see a "contract us" @ hfsignals.com...

Kelly K5AID?


Sent from my Verizon, Samsung Galaxy smartphone
Re: Which version of the ubitx board is currently shipping?

Kelly Mabry
 

Thank you so much!

Kelly K5AID?
Re: Which version of the ubitx board is currently shipping?

 

开云体育

Yes as of a few weeks ago, Farhan posted this info to the group.

Skip Davis, NC9O?

On Mar 8, 2019, at 23:28, Kelly Mabry <kmabry2007@...> wrote:


Just to ask, is the V5 board shipping as of today? Sorry for the question? here, I did not see a "contract us" @ ...

Kelly K5AID?


Sent from my Verizon, Samsung Galaxy smartphone
Re: Should I wait to buy a ubitx?

Jack Purdum
 

Something else to consider: Al and I have build a number of ?BITX's as have members of our Builders Group. All of them that we know about are within spec on 80M and 40M. All were also on spec on 20M, but 2 were "on spec", but close enough that it might be within or outside of spec on a lab SA. Both of those, however, were within 1.96σ.

So, if you only have an antenna for 80 and 40 meters, it's likely a moot question. If you plan to work 20M and below, I'd say buy it and see if it's in spec or not. If not, chances are you can sell it on this Forum for close to what you paid for it.

I'd hate to see you pass up the enjoyment this little rig can afford you. You're going in with your eyes open and if it doesn't make you happy, you have a plan for recouping the lion's share of your cost. What the heck...Custer took a chance...

My $0.02 are in the ring...stepping down from soapbox...

Jack, W8TEE

On Friday, March 8, 2019, 11:02:57 PM EST, Brutus Laurentius <markhamfarm14@...> wrote:


We all have our biases, which include maybe a bit of projection ... and I'm projecting that this is a fun kit well worth buying.

Now, in saying that, I am pretty handy with a soldering iron and hot air too, along with magnified goggles and good lighting.??

Like anything this fun, there are a lot of ways to approach it.? But the thing is, this radio is very hackable.??

I believe, especially if you adjust Rv1 for 5 watts and do the other calibration required, you won't be getting cited by the FCC.

My experience is with a V4 with all the ubitx.net "fixes" plus I? incorporated most of the changes (except for the IF frequency change) from the V5, as well as replacing the driver transistors, etc.? I ultimately put the filters on a little daughter card on top of the originals.? Next I'll be adding agc.

I happen to have access to a spectrum analyzer at work, and with that done, as long as I kept the output below 7.5 w on my band of choice, I had nothing that was a problem.? ?

A bit of patience, tweaking and fun, and at least for me, the rig has turned out usable!
Which version of the ubitx board is currently shipping?

Kelly Mabry
 

开云体育


Just to ask, is the V5 board shipping as of today? Sorry for the question? here, I did not see a "contract us" @ hfsignals.com...

Kelly K5AID?


Sent from my Verizon, Samsung Galaxy smartphone
Re: Should I wait to buy a ubitx?

Kelly Mabry
 

Brutus, you have said the magic words....hackable.? This has me hooked. Indeed, I will be ordering the? radio next month or so..due to finances. No I won't be selling my ts 590sg, hi hi.?

I welcome the things that I have learned from researching this radio... and all of you..on this thread. You CAN teach an old ham new tricks. Like the 9:1 un un I plan to build to utilize a long wire with the ubitx. Considering things like a tuner and or swr homebrew devices for qrp.

73,?

Kelly K5AID?
Re: Should I wait to buy a ubitx?

 

We all have our biases, which include maybe a bit of projection ... and I'm projecting that this is a fun kit well worth buying.

Now, in saying that, I am pretty handy with a soldering iron and hot air too, along with magnified goggles and good lighting.??

Like anything this fun, there are a lot of ways to approach it.? But the thing is, this radio is very hackable.??

I believe, especially if you adjust Rv1 for 5 watts and do the other calibration required, you won't be getting cited by the FCC.

My experience is with a V4 with all the ubitx.net "fixes" plus I? incorporated most of the changes (except for the IF frequency change) from the V5, as well as replacing the driver transistors, etc.? I ultimately put the filters on a little daughter card on top of the originals.? Next I'll be adding agc.

I happen to have access to a spectrum analyzer at work, and with that done, as long as I kept the output below 7.5 w on my band of choice, I had nothing that was a problem.? ?

A bit of patience, tweaking and fun, and at least for me, the rig has turned out usable!
Re: Should I wait to buy a ubitx?

 

There nothing call FINAL / ULTIMATE in any walk of hobby. Designs evolve sorting shrtvommings of previous, adding extra facilities, etc.
IMHO, THERE IS NO POINT WAITING .?

Obviously cost of making a rig would tend to go northwards, as material cost increases.
V5 had solved many issues. Carrier supression is to be checked after aone or 2 calibration cycles. Calibration itself is not a difficult task.

At hobby level most of us can't afford all T&M equipment at home.

Thise who have are already serving the hams with their tests and improvement mods. We can perhaps implement them.

All the best
Sarma
vu3zmv

On Sat, 9 Mar 2019, 8:23 am Kelly Mabry <kmabry2007@... wrote:
On Fri, Mar 8, 2019 at 06:37 PM, Dexter N Muir wrote:
Oh FGS, peeps. Buying a KIT does NOT get you a commercial RIG - it gets you the basis on which to work. I have a Bitx40 that I've never really got working in years (#4/9126V?). I might have, had I sussed out the whole-of-HF S8 interference. Help from the R.I tracked that to my disused VHF FT227 still powered up, but by then I'd taken down the dipole. I couldn't get hold of a 2N700-type FET to quell the Tx/Rx thump (I tried a transistor scheme that didn't work over 3 or 4 iterations), and won't get to it 'til I can afford some (I don't control the purse strings, and we have other more urgent (family) matters to deal with) - and the time and space to work on it, but I WILL! (and possibly AGC too). The love of RF - the very definition of "amateur Radio" - is in my very bones! Unless you go QRO with externals, the Bitxes are functional as presented. Spurs and harmonics? Piffle! GOTA! What nearby would likely be affected, let alone detect ithem?
73
Dex, ZL2DEX

?Gordon, I understand? your point.? Being disabled, I no longer have the resources for buying ready built gear. It takes months to squeeze? $$ for anything over $100 to$200.

And Dexter, I am not saying this radio should equal a kenwood. Far from it.? I expect to struggle and modify this...I thrive on it. This is no noob ham here.? I am just getting opinions and logically proceeding. I am amazed at the work contributed in this group, et. al.?
73,
Kelly? K5AID?

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