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offset on Raduino

OZ9AEW
 

how much offset is needed on other Bitx40 ?
when my display show 7.0320 the "real" freq is 7.0285MHz !!! I have use a Pixie with 7.030MHz X-Tal as ref.?
when it comes to Birdie on 7.199 it is on 7.210?
I am not sure about my freq.counter but if Raduino is programmed to deliver a 25MHz signal my reading is 25.0052MHz
Re: uBITX - A reboot of the old BITX

Trent Trent
 

Does anyone know when the ubitx will ne sold yet?

On 21 Jun. 2017 6:49 am, "Ashhar Farhan" <farhanbox@...> wrote:
you can buy about 50 crystals for a few dollars and sort them out.


- f?

On Wed, Jun 21, 2017 at 1:35 AM, terryhugheskirkcudbright via Groups.Io <terryhugheskirkcudbright=[email protected]> wrote:
hi

i am interested in the ubitx and may build one from scratch but the problem is getting a set of matched crystals for the filter.

is there any supplier that can supply matched crystals.

terry


Re: uBITX - A reboot of the old BITX

 

you can buy about 50 crystals for a few dollars and sort them out.


- f?

On Wed, Jun 21, 2017 at 1:35 AM, terryhugheskirkcudbright via Groups.Io <terryhugheskirkcudbright@...> wrote:

hi

i am interested in the ubitx and may build one from scratch but the problem is getting a set of matched crystals for the filter.

is there any supplier that can supply matched crystals.

terry


Re: 3D Printer Suggestions

 

I second this.? Simplify3D is fantastic.

On Jun 20, 2017 3:27 PM, "Michael Hagen" <motdog@...> wrote:

Simplify3D?? I guess.? Best $149 I spent!? You won't believe how fast it slices you model and puts in on the SD card!

They are adding every printer model they can find.

You basically get a license for 2 computers.? I think if you remove it off them you go back to 2 max.

I still have a HD somewhere I need to get it off of to bump my count back in case I need it on my laptop?


On 6/20/2017 1:10 PM, DJ2AG wrote:
Michael, do you mean Simply3D or?simplify3d?

Re: 3D Printer Suggestions

 

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Simplify3D?? I guess.? Best $149 I spent!? You won't believe how fast it slices you model and puts in on the SD card!

They are adding every printer model they can find.

You basically get a license for 2 computers.? I think if you remove it off them you go back to 2 max.

I still have a HD somewhere I need to get it off of to bump my count back in case I need it on my laptop?


On 6/20/2017 1:10 PM, DJ2AG wrote:

Michael, do you mean Simply3D or?simplify3d?

Re: Easy low pass filters by qrpkits

 

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First put the scope with (AC coupling Set) on the generator output, get a voltage (p-p Peak to Peak is fine). Then while monitoring that

point, put 50 Ohms across generator and scope probe.? If it goes approximately in half, you are in good shape.

The connect Gen to input of the filter, 50 Ohms and scope to output.? Try going 5 - 10 MHz and plot the output.

You might want to first watch the input voltage over that frequency range.? You hope it does not change much.

If it does you will have to subtract or add input changes to you output voltage plot.

Go for it.? It is exciting to do this stuff!? A hell of a lot better the watching the News!

Mike, WA6ISP


On 6/20/2017 12:52 PM, EA3IAV wrote:

Ok i have s dummy load of 50ohm

this would be the thing

signal generator - filter in - probe of the oscilloscope in the vcc of the filter OUT-dummy load?

??

which signal? If i input 7mhz it will let it pass i guess

Re: 3D Printer Suggestions

 

Michael, do you mean Simply3D or?simplify3d?
Re: Easy low pass filters by qrpkits

 

I use the QRP labs relay kit for homebrew radios works very nice. Below is the almost finished version I have now. 5V and do upto 5 bands or all of them if you switch them out. Listed to handle 10W max.

http://shop.qrp-labs.com/ULPF
Re: uBITX - A reboot of the old BITX

 

hi

i am interested in the ubitx and may build one from scratch but the problem is getting a set of matched crystals for the filter.

is there any supplier that can supply matched crystals.

terry
Re: 3D printed knobs

Matt Patterson
 

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I have a Monoprice Mini and a Monoprice Select Plus. ?Both are excellent printers.

Matt

Sent from my iPhone 7

On Jun 20, 2017, at 8:41 AM, R S via Groups.Io <rons8@...> wrote:

What 3D printer are you folks using and sites or are they purchased locally to you? ?What are they priced at?

Thanks
Ron. KJ4FFG?




On Tuesday, June 20, 2017, 09:25, Michael Hagen <motdog@...> wrote:

I also used supports, the big Knob is hollowed out some places. I made
2, both came out perfect.? Simply3D makes me an Expert!

Takes a exacto knife to dig out the supports.

I love that program.? If you don't have a 6-32 tap, you can heat up a
long 6-32 screw (held in vice grips) and thread the holes.

Mike, WA6ISP
Re: 3D Printer Suggestions

Matt Patterson
 

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I have a Monoprice Mini and a Monoprice Select Plus. ?I printed the case on the plus. ?

Matt

Sent from my iPhone 7

On Jun 20, 2017, at 10:06 AM, Doug W <dougwilner@...> wrote:

That looks like a great deal.? I bought a printrbot simple metal when they first came out.? I am still very happy with it but I tell everyone that asks you can do as good or better for less money.? Looks like this is another one that proves that.

Re: Easy low pass filters by qrpkits

EA3IAV
 

Ok i have s dummy load of 50ohm

this would be the thing

signal generator - filter in - probe of the oscilloscope in the vcc of the filter OUT-dummy load?

??

which signal? If i input 7mhz it will let it pass i guess
Re: Easy low pass filters by qrpkits

 

¿ªÔÆÌåÓý

You need to test it with 50 Ohm load (a short leaded resistor or SMD).? The generator needs a 50 Ohm output, that may be the major problem.? Use 100 MHz scope and good x10 probe.

If you have a signal generator that goes to 7MHZ.? Load it with the 50 ohm resistance.? The non-loaded value on the scope should go to 1/2.

That would be good, the generator has 50 Output Z.?

Mike, WA6ISP


On 6/20/2017 12:39 PM, EA3IAV wrote:

I do have an oscilloscope. I may inject rf signals and see if they are neutralized right?

Re: Case

 

Wow, everybody else's BITX looks so much better than mine, and I tried so hard to avoid the "homemade" look!? Haha!


--
Darren, W9ZIM
Re: Easy low pass filters by qrpkits

EA3IAV
 

I do have an oscilloscope. I may inject rf signals and see if they are neutralized right?
Re: Easy low pass filters by qrpkits

 

EA3IAV

Test or evaluation of filters when you have very limited test equipment is not an insurmountable
obstacle. Build a diode probe or RF detector to use with your DC voltmeter to measure output
of the filter.? Build a reasonably stable oscillator that covers the frequency of interest.? Input this
signal into the filter and measure and record the output as you tune across the filter passband
in 100 Hz steps.? Then write those readings on graph paper for voltage based reporting, and on
log paper for db based reporting.

Arv
_._

On Tue, Jun 20, 2017 at 1:27 PM, EA3IAV <Cesarleon@...> wrote:
Are this kits any good?
i have purchaed the 40m version to check it up. How can i test its performance? I have an oscilloscope but ?I am total noob with it. It has signal generator too
I see no big difference using it

?It is cheap ($15) and easy to build. Most conplicated thing is taking the whole thing in an alu box. I guess it may be installed inside the bitx too
Easy low pass filters by qrpkits

EA3IAV
 

Are this kits any good?
i have purchaed the 40m version to check it up. How can i test its performance? I have an oscilloscope but ?I am total noob with it. It has signal generator too
I see no big difference using it

?It is cheap ($15) and easy to build. Most conplicated thing is taking the whole thing in an alu box. I guess it may be installed inside the bitx too

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BITX QSO Night, Sunday, June 25, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere

 

BITX QSO Night, Sunday, June 25, 7pm Local Time, 7277 kHz in North America, 7177 kHz elsewhere

Join us as we make contacts from BITX40 to BITX40 on 7.277 MHz in 40 meters!

To participate, call CQ BITX at 7pm sharp, your local time, on Sunday. Call off and on for about 15 minutes. It is helpful if you call CQ BITX with your name and location.? Repeat your call a number of times if conditions are weak.

This is a worldwide event at 7pm in each time zone.? You may participate in any time zone, regardless of your location, so you may wish to call in at 6pm, 7pm and 8pm, your local time, to contact hams in adjacent time zones.

The backup frequency in case of QSB or other noise is 7210 kHz.

Report your QSO's, discuss propagation, noise, signal reports, audio reports, antenna type, etc. in this thread.

This is an undirected, scheduled event.? The BITX QSO Night relies on you to call CQ BITX to initiate contacts with other stations, so warm up that final and transmit a few calls at 7pm on Sunday.? Talk to you then!
Re: Testing a new board PA

 

Oh, I forgot to mention, that is with 24V on the PA.

My plan is to get the new board up and running and then I can compare the voltages etc. between the two and try to figure it out. And no, I don't mind a bit, I have a lot to learn.

On 6/20/2017 7:51 AM, Raj vu2zap wrote:
Jonathan, I would consider 5W within limits.

Let me tell you a condensed story!

My Ft757Mk2 was on 10M CW. Nice pileup. Then I heard a bad tone so I gave him a T5 and he did the same. I shut down.
I opened the rig and probed and all was fine. The rig did the same after some time.
I finally realized that the PLL lost lock and was creating noise hunting for a lock.
I found the signal in the feedback loop was low when board was hot.
I figured that the loop gain was low. I just swapped some 2SC535 as I remember from other parts of the rig and
Problem solved.

Sometimes a combination of semiconductor parts results in such situations! If everything works then we don't learn anything new!

Cheers
Raj

At 20/06/2017, you wrote:
Raj,

Thanks. Low mic gain might be it, but I thought you should get 5W out of the simple electret mic included?

And the issue is that I have to crank R136 fully over to get the 5 watts. I will short out R131 and see what happens.

JOnathan

On 6/19/2017 10:43 PM, Raj vu2zap wrote:
Could be due to any or many of the following reasons:

1: Low audio drive - very likely (I use an amped Motorola mic and it goes up to 10W)

2: Low VFO or BFO levels

3: BFO frequency may need tweaking to suit the filter or your voice.

4: Low BiDi amp stage gain - unlikely

5: Low gain in final RF amp stages - short out R131 and see

Considering you get 5W it is not really low as you think!

Cheers
Raj

At 19/06/2017, you wrote:
HI All,

My original BITX never "aligned" correctly. In order to get the 1 amp current draw when hallooo'ing into the mic I had to crank R136 all the way. In that way I could get 5 watts out but only if running higher PA voltages.

xxx snip xxx

Thanks!

Jonathan - KK6RPX
Re: 3D Printer Suggestions

 

That looks like a great deal.? I bought a printrbot simple metal when they first came out.? I am still very happy with it but I tell everyone that asks you can do as good or better for less money.? Looks like this is another one that proves that.
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