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Big problems with 2 Max Pro I kits

 
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Big problems with 2 Max Pro I kits
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nashovsky
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Joined: 26 Aug 2003
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Post Big problems with 2 Max Pro I kits Reply with quote
Hello I have two Max Pro 1 kits that I put together, I will call them #1 and #2

on #1 , the LCD does not work . (it does not work when plugged to #2 either). I seem to have RF power, as the dummy load and output transistor are getting warm (and the SWR meter moves). It draws a 0.45A current at 12 volts.
With an FM receiver I can tune in to 94.5 MHz (always this frequency) and hear the audio quite clearly ...
IS there something wrong with the micro-controller ? is there a way to reset the program and RAM ? But note : If I put the LCD from #2 (which works) on #1 it does not work either....so #1 cannot drive an LCD...

on #2, the LCD does work, I get the welcome message, can change frequency up and down no problem.. I can hear the audio clearly with an FM receiver BUT I have no output power, the load and transistor stay cold.. and the SWR does not move... It draws a 0.15A current at 12 volts.
Besides, when i do a "tune-up" I can hear a very high pitched sound , but turning C24 and C25 or compressing inductors does change the pitch at all.. ??
A test once gave me VCO ok but now is telling me 0-Compress L7, 1-Error..

I have been very careful when assembling the components, I dont see any errors..... I suspect faulty components...sorry
To summarise : I have one kit with a dead LCD, one which has no RF power and cannot be tuned and the other one has RF power put cannot work with an LCD..

PLEASE HELP!
Getting frustrated here.
Mon Mar 22, 2004 2:25 am View user's profile Send private message
pcs
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Joined: 18 Jan 2002
Posts: 3063
Location: Radio Land

Post Reply with quote
First, such posts do not belong in this forum. Weeks could easily
go by before anyone reads this post and answers. That's why we have
email and feedback for posted at the website.

One problem with KITs is that it is possible to make a mistake
while assembling them. MAX PRO I is not that easy to assemble.
It is easy to make a mistake.

Builders who claimed to be professionals have had problems in the past
and upon inspection of the returned KITs I found that they were totally
incompetent (14 year kid would do a better job).

For now this:
- Check the contrast trimmer. You need to turn it to have the LCD display
something.
- Check the components around xtal on LCD board.
- Check the bridge on the LCD board as per instructions
- On RF board make sure 56 ohms resistor close to VCO coil is 5-10mm
above the PCB and close to the VCO

For more info use our email and include more detail, perhaps even a photo.

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Mon Mar 22, 2004 11:06 am View user's profile Send private message Visit poster's website
nashovsky
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Joined: 26 Aug 2003
Posts: 5

Post all sweet Reply with quote
Just to let you know that all my problems have now been fixed and were due to my mistakes

The kit with no RF power.. had a bad solder on one of these tiny RF transistors.

The other kit which had problems with the LCD, had its 7805 regulator fried, this is because when you mount the LCD screen into a metal box, it can shortcut the connections at the front of the LCD (badly designed LCD I have to say). So put a lot of electrical insulation tape around the LCD ! This is quite important and I think should be added in the manual. Should also be added how to connect the LCD connector the right way. I had to guess from pictures..

Last thing: I did my first TX trial yesterday and got a 20km+ perfect transmission with a 1/4 wave antenna. I'm Happy
Fri Mar 26, 2004 4:17 am View user's profile Send private message
Sir Nigel
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Post Re: all sweet Reply with quote
nashovsky wrote:
got a 20km+ perfect transmission with a 1/4 wave antenna.


Umm, WOW!

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Fri Mar 26, 2004 5:49 am View user's profile Send private message Visit poster's website
pcs
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Joined: 18 Jan 2002
Posts: 3063
Location: Radio Land

Post Reply with quote
Buy a boxed unit and all these things will be taken care of
by our team

_________________
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
Fri Mar 26, 2004 9:21 am View user's profile Send private message Visit poster's website
nashovsky
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Joined: 26 Aug 2003
Posts: 5

Post Reply with quote
Well, I like my soldering iron
Mon Mar 29, 2004 1:09 am View user's profile Send private message
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