Re: Making PSK31 Contacts
I would try to improve the heatsinking. The case provides a lot of area to dissipate the heat but it has to funnel all that heat through fairly thin sheet metal. I would attach a largish finned heatsink on the outside. This will give it a thicker chunk of metal to conduct the heat away and much more surface area, close to the source, to dissipate the heat. It needs to have good metal to metal contact (with a thin layer of thermal grease between) with the metal case. Ideally the PA transistor would be attached directly to the heatsink through a hole in the case.
Clark Martin
KK6ISP
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On Jun 8, 2017, at 8:25 PM, Jeff <jeff@...> wrote:
Ok finally got the Vox board adjusted and hooked up the laptop power supply. I have about 19v on the PA and am getting about 9-10 watts out. Plugged in the computer this evening and was able to make several contacts on PSK31. Seems to be working fine my only concern is the PA is getting pretty warm even though it is heatsinked to the rear case. I will have to watch it closely and see what happens.A fan may be in order. Thanks to all for the guidance.
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It appears to be the same part as the 1n4148w diodes used in the diode ring mixer, in an SOD-123 package: ? However, if you reversed the power supply leads into your Bitx40, you could have blown just about all of the semiconductors on the board. You might wind up having to buy a new Bitx40, use this one for spare parts. Another issue is giving a few volts over 12v, since Q13 and R141 are already a bit beyond their maximum dissipation limits. Adding an LM2940T-12 as per ?? /g/BITX20/message/26492
would protect from both reversed supply leads and voltages beyond 12v. ?It also limits current to something manageable. Perhaps something like this should be included in the board layout if it rolls (or in the uBitx). Jerry, KE7ER
On Fri, Jun 9, 2017 at 03:55 am, <mattcarus@...> wrote:
Powered up my BITX40 last night and some smoke escaped from D6 :( - I assume it'll need replacing which is fine, can anyone tell me what package size it is?
?
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Or if you have access to a 3d printer....;.
https://www.thingiverse.com/thing:1012950
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See if this works, I found some hard to parts and even a complete front panel for a damaged icom rig!
See under new parts for June - you need only the plastic bits and you can bend a brazing rod to fit your box size.
Cheers
Raj
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At 09-06-2017, you wrote: i m looking for a nice way to tilt on my radio boxes in order to make it more confortable to use.
maybe a bracket or folding legs to put under the box
Any hint? I have tried a lot of different searches on ebay and amazon. No joy
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Re: Dhl customs cost to the usa
I was robbed 41 eur by DHL in OH.
They charge 20eur, if you handle the customs declaration by yourself, and 24 eur, if you decide let them handle it.
Makes no sense.
Timo OH7LMQ
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Do you want them permanent or flip-up? If permanent is ok, just screw a
couple pieces of Delrin to the bottom for front legs. If you want
flip-up, look at getting a couple from an old keyboard. Depending on what
they look like and how they work will dictate how you mount them to your
box.
Vince.
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Yeah this is more or less what i am looking for. Probably buying the whole
case will cost just about the same as the pegs only
--
Michigan VHF Corp.
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Yeah this is more or less what i am looking for. Probably buying the whole case will cost just about the same as the pegs only
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. If you look at the 2nd to last picture, you can see how the legs work. It's pretty simple.
--
John - WA2FZW
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Re: Dual Band BITX40: Automatic Switching from 40m to 80m
I like this !
I'm planning to do the same thing, because now?I have two qrp transceivers to take along travelling(MST2 for 80M). I also looked the same vfo you have used.
Is it possible to?do both usb/lsb with ithis vfo?? I like working digital modes, and need usb as well.
If it has 2 selectable oscillator frequencies, one could use it as carrier osc and switch sidebands easily.
For spurious , i'm planning to make a switchable filter between antenna connector and the bitx board. this comes along when the rig is in 80M and bypassed when in 40M.
Timo OH7LMQ
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 i m looking for a nice way to tilt on my radio boxes in order to make it more confortable to use. maybe a bracket or folding legs to put under the box Any hint? I have tried a lot of different searches on ebay and amazon. No joy
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Powered up my BITX40 last night and some smoke escaped from D6 :( - I assume it'll need replacing which is fine, can anyone tell me what package size it is?
I promise I'll double-check the wiring in future...
Matt 2E1HNK
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Dual Band BITX40: Automatic Switching from 40m to 80m
Hello everyone, I've been working diligently on my dual band BITX40 conversion. It can now switch, automatically, between 40 and 80 meters. I wrote it all up on my blog with several pictures: http://miscdotgeek.com/bitx40-dual-band-conversion/-- Ryan Flowers W7RLF
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?<-- Learn how to go digital on the BITX40
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Re: BITX40 - convert to 20 meters
Check out my blog below, I now have that post up:? http://miscdotgeek.com/bitx40-dual-band-conversion/ -- Ryan Flowers W7RLF
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?<-- Learn how to go digital on the BITX40
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With the raduino you will have to enable USB and it'll switch the VFO to +12mhz offset instead of -12mhz offset. I did this on my BITX40 though I use the QRP Labs VFO. The principal is the same. You do have to remove C91 and C92 to make it work: -- Ryan Flowers W7RLF
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?<-- Learn how to go digital on the BITX40
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Re: Calling all Midwesterners.
It just came to me. it's something like "CQ Texas BITX40, or whatever state you want. Just like specific DX countries. Sometimes you gotta ask the question out loud to someone to figure it out for yourself.?
Right, next Bitx40 QSO night I am gonna try calling the states around me, and some of this list we have so far. Watch out Jack, I noticed you were on that list too. I'm calling for ya pal. Hi,Hi.
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Re: Calling all Midwesterners.
So, how does one go about calling for near by contacts, or even certain areas of the country. Like, what is the opposite of CQ DX? My intent is to call for BITX'ers closer to me that I have better luck hearing.
I noticed most of the middle of the country BITX'ers are closer to the North East. Are there any Texans? My antenna seems to attract Texans. All whopping three QSO cards I have are from Texas.
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Ok finally got the Vox board adjusted and hooked up the laptop power supply. I have about 19v on the PA and am getting about 9-10 watts out. Plugged in the computer this evening and was able to make several contacts on PSK31. Seems to be working fine my only concern is the PA is getting pretty warm even though it is heatsinked to the rear case. I will have to watch it closely and see what happens.A fan may be in order. Thanks to all for the guidance.  
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Re: The $19 DIY DSP audio filter
Nice project. ?
Note that it runs under the Arduino environment.
So Allard's sketch should compile on it with little fuss, run alongside the filters.
WIth display and Si5351 breakout board, could replace the Raduino.
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On Thu, Jun 8, 2017 at 03:16 pm, EA3IAV wrote:
It may work?nicely inside our bitx40
?
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That is useless as i have a rotary encoder
On 9 Jun. 2017 11:34 am, "John Smith via Groups.Io" <johnlinux77= [email protected]> wrote: Our groups Raduino Rock Star Allard has put together a package for us, read the instructions. Hear is the link.
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Raj vu2zap
Matt Carus
Jeff