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#v6 need a 12v connectiion #v6

 

These points have 12V on them when in transmit mode, according to the schematic for a V4 (and should be the same for later designs):

R89, side opposite of C86

U2 Pin 3 (near the 3-pin power connector. It's little.)

R66, side opposite of R65

R84, opposite side from C83

D11 junction with C154

D12 junction with C156

D13 junction with C158


Test with a voltmeter first, of course!? Being as some fans can introduce noise into circuits from which they're powered, the latter three might be worth trying first, as they chiefly operate relays rather than tuned RF circuitry.? I took power from K1 Pin1, but that requires getting to the bottom so that's apparently out; The above points feed from that point anyway.



Ted
K3RTA
 

Ralph,
I used P1 (which is a 12 v supply) to run my cooling fan. The middle pin is V+, the pin closest to the edge of the board is ground. Not sure what the other pin is for but I didn¡¯t need it for the fan.
--
?

73
Mick VA3EPM?
 

Hi Ralph a meter could tell you what you want to know about your power source.

Definitely test the fan running off your radio power supply for electric noise. The worst offender I had was a small squirrel cage fan. On most of the units I had designed a duct to direct the air into the heat sink area . Here was the offensive fan.
?

I thought the duct was cool and fit in the space. Spent a lot of effort ciphering the fan mount without trying the fan first.?

Perhaps like a lot of 3d designers I put my prototypes on thingiverse.? The best solution I have found for uBITX heat is attaching the power transistors to large heat sinks or with isolation, to the aluminum case. No noise or extra power consumption and heat is dissipated.
--
73
Dave
 

I just finished constructing my full kit uBitx v6 and powered it up with a 12v- 1amp wall wart. When?I connected?to my Mag Loop antenna, I did not receive voice nor CW. However, all the icons on the display appeared to work correctly. My problem was when I pressed the PTT on the mic, I did not get a TXT?icon lit up. I am left with one of 3 possibilities -?
1 the antenna does not work (not very likely)
2 the problem lies with the mic (possible?)?
3 the txmitter has a problem (possible but I have no way to verify)
How can I verify which one is the problem, and then get it fixed??

Thanks,
Larry (N8MGU)

On Thu, Apr 2, 2020 at 12:05 PM _Dave_ AD0B <davesters@...> wrote:
Hi Ralph a meter could tell you what you want to know about your power source.

Definitely test the fan running off your radio power supply for electric noise. The worst offender I had was a small squirrel cage fan. On most of the units I had designed a duct to direct the air into the heat sink area . Here was the offensive fan.
?

I thought the duct was cool and fit in the space. Spent a lot of effort ciphering the fan mount without trying the fan first.?

Perhaps like a lot of 3d designers I put my prototypes on thingiverse.? The best solution I have found for uBITX heat is attaching the power transistors to large heat sinks or with isolation, to the aluminum case. No noise or extra power consumption and heat is dissipated.
--
73
Dave



--
GnuPG Public Key ID: DC840312
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Never cross a Dragon, for you are crunchy and taste delicious!
My Interests are:
Ham Radio (N8MGU) | Opera | Theater | Sailing | Judaica | CKCS
 

Once you get your antenna figured out, you will want a bigger power supply. The sag would be significant. As would be the electric noise.
--
73
Dave
howard winwood G4GPF
 

One amp is not enough, you need a 3 amp supply to give a little head room.


On Fri, 3 Apr 2020, 04:38 _Dave_ AD0B, <davesters@...> wrote:
Once you get your antenna figured out, you will want a bigger power supply. The sag would be significant. As would be the electric noise.
--
73
Dave
 

Before I spend my money on a power supply, can I use a switching supply or will that be too electronically noisy>
Thanks.
Larry (N8MGU)

On Fri, Apr 3, 2020 at 3:10 AM howard winwood G4GPF <winwoodh@...> wrote:
One amp is not enough, you need a 3 amp supply to give a little head room.

On Fri, 3 Apr 2020, 04:38 _Dave_ AD0B, <davesters@...> wrote:
Once you get your antenna figured out, you will want a bigger power supply. The sag would be significant. As would be the electric noise.
--
73
Dave



--
GnuPG Public Key ID: DC840312
==============================================================

==============================================================
Never cross a Dragon, for you are crunchy and taste delicious!
My Interests are:
Ham Radio (N8MGU) | Opera | Theater | Sailing | Judaica | CKCS
[email protected]
 

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Has anyone found an off the shelf wall wart that powers the xcvr?

Get

From: [email protected] <[email protected]> on behalf of Larry Mittman <larrymittman@...>
Sent: Friday, April 3, 2020 11:35:50 AM
To: [email protected] <[email protected]>
Subject: Re: [BITX20] #v6 need a 12v connectiion
?
Before I spend my money on a power supply, can I use a switching supply or will that be too electronically noisy>
Thanks.
Larry (N8MGU)

On Fri, Apr 3, 2020 at 3:10 AM howard winwood G4GPF <winwoodh@...> wrote:
One amp is not enough, you need a 3 amp supply to give a little head room.

On Fri, 3 Apr 2020, 04:38 _Dave_ AD0B, <davesters@...> wrote:
Once you get your antenna figured out, you will want a bigger power supply. The sag would be significant. As would be the electric noise.
--
73
Dave



--
GnuPG Public Key ID: DC840312
==============================================================

==============================================================
Never cross a Dragon, for you are crunchy and taste delicious!
My Interests are:
Ham Radio (N8MGU) | Opera | Theater | Sailing | Judaica | CKCS
 

I had tried a couple that I had, including a "lab grade" 5 amp power supply, all had issues with noise.? I then bought?

And it too had noise issues even worse than the others I had tried.

I finally bought a true "ham" grade 13.8 volt supply, and then another.? These were the only solution that really had acceptable results.? Both are WAY overkill for just a uBiTx, they were bought to power multiple low power radios and one 100 watt Icom.

Others have reported success with lower-cost supplies.? I would suggest that you wait for one of them to respond.? I would recommend that you do not just buy one that seems ok.? Sometimes cheap becomes more expensive that good.

FWIW
73
Evan
AC9TU
 

Most Dlink router wall warts are capable as they are 12V/2.5A

--
Ion

VA3NOI
 

?Not all of those wall warts are regulated, as I found out.
?Need to test unloaded voltage against loaded voltage.
?Many 12 volt wall warts put out 16 or more volts at no load. This you do not want.

?Wayne WA2YNE

On Fri, Apr 3, 2020, 12:41 PM Ion Petroianu, VA3NOI <ion.petroianu@...> wrote:
Most Dlink router wall warts are capable as they are 12V/2.5A

--
Ion

VA3NOI

 

Some of the wall warts seem to be DC regulated, but put out very large pulsating voltage.? They?
generate all kinds of hum on receive and the transmitted signal looks very dirty on a spectrum analyzer.

Ralph ku4pt


On Sun, Apr 5, 2020 at 10:05 PM Wayne Leake <wayneleake@...> wrote:
?Not all of those wall warts are regulated, as I found out.
?Need to test unloaded voltage against loaded voltage.
?Many 12 volt wall warts put out 16 or more volts at no load. This you do not want.

?Wayne WA2YNE

On Fri, Apr 3, 2020, 12:41 PM Ion Petroianu, VA3NOI <ion.petroianu@...> wrote:
Most Dlink router wall warts are capable as they are 12V/2.5A

--?_

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