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HR2510 Front end overload.
- Thread starter Low_Boy
- Start date
Ah...
Hmm...
Did you ever check to see if you have TWO modes on at one time in Receive?
I mean, it can happen but - Check your SSB/AM/FM switching transistors - make sure they check out too.
Because if one can't turn off then you have a mixing mess in there and that radio can't handle that...
Hmm...
Did you ever check to see if you have TWO modes on at one time in Receive?
I mean, it can happen but - Check your SSB/AM/FM switching transistors - make sure they check out too.
Because if one can't turn off then you have a mixing mess in there and that radio can't handle that...
Attachments
Then there's it's diode mess...
Front Panel facing you - right by TP1 resistor in previous photo graphic - underneath that harness - there is a header in that area that is all the selected features and the "Diode breakout" for power steering - a Diode Matrix to route the selected mode to the proper sections.
That's why you needed that voltage chart - the end point transistors can offer clues as to how far back you need to trace the matrix if you needed to.
IF you find a Blown transistor - it may mean the Matrix - one up to several diodes, may have failed and sent over 8 volts to the Base of that transistor - blowing it. Those are the easy ones. In the other direction of approach, you may find the Transistor may be ok, but your DIODE sending power to it - found being blown open, you just don't have a way of turning off a section uless you pull that part controlling it- which is why I posted the suggestion above.
In those cases, just remove the transistor for checking - and simply power up the radio see if the CONDITON STILL EXISTS - if it stops working in that MODE - switch to another mode and observe the results. See if it will operate normally- if it does, you found the area. But check the transistor and follow the traces back to the diodes in that Matrix. RX side transistors - like the charts above - will help you locate the right ones...like Q113 (AN612) or Q108 - (IF AMP L105) those two are likely to show similar symptoms to yours if they are not working like they should.
Look at the Diode matrix above, you can do the same thing on the Diodes - the farther away ones are the easiest to cheek one way not the other - it's as you get closer to the Matrix the Didoes from one trace can interfere with your ability to locate...
So, then do a continuity check FROM the HEADER - to the Transistor your suspecting...
That Transistor chart is the guide to this, using the MODE, follow down the row your transistor is in to locate the column to show voltage.
Front Panel facing you - right by TP1 resistor in previous photo graphic - underneath that harness - there is a header in that area that is all the selected features and the "Diode breakout" for power steering - a Diode Matrix to route the selected mode to the proper sections.
That's why you needed that voltage chart - the end point transistors can offer clues as to how far back you need to trace the matrix if you needed to.
IF you find a Blown transistor - it may mean the Matrix - one up to several diodes, may have failed and sent over 8 volts to the Base of that transistor - blowing it. Those are the easy ones. In the other direction of approach, you may find the Transistor may be ok, but your DIODE sending power to it - found being blown open, you just don't have a way of turning off a section uless you pull that part controlling it- which is why I posted the suggestion above.
In those cases, just remove the transistor for checking - and simply power up the radio see if the CONDITON STILL EXISTS - if it stops working in that MODE - switch to another mode and observe the results. See if it will operate normally- if it does, you found the area. But check the transistor and follow the traces back to the diodes in that Matrix. RX side transistors - like the charts above - will help you locate the right ones...like Q113 (AN612) or Q108 - (IF AMP L105) those two are likely to show similar symptoms to yours if they are not working like they should.
Look at the Diode matrix above, you can do the same thing on the Diodes - the farther away ones are the easiest to cheek one way not the other - it's as you get closer to the Matrix the Didoes from one trace can interfere with your ability to locate...
So, then do a continuity check FROM the HEADER - to the Transistor your suspecting...
That Transistor chart is the guide to this, using the MODE, follow down the row your transistor is in to locate the column to show voltage.
- - easiest way to do it for quick check. But be careful and set your mode switch to one setting - then another opposite side setting, to check the Diodes and the switch matrix to make sure that they are not messed up
- - again a Short/blown route from the switch to the board can affect operation.
Last edited:
@Low_Boy -not to be a PITA
But this too can help you with the Header and backprobing it...
Get one of these...
If you own a car, you prolly' already have one, these are the OLDER style 6-24V - circuit testers. The ones that use a bulb versus LED types.
Why Bulb? Because of it's non-directional properties. It lets current flow thru both directions. LED are diodes one-way devices - so to check that header, you'll need the one that has that bulb - looks like a lantern type
Now, you'll need it for your Header check...
You'll need to power up the radio for this so you can let the HEADER power the light and show you what does work and what isn't...case ground will be fine for that alligator clip - this is not an insulated chassis radio...
Best results here are to write down your color code to position on the header - for this will help you find out where to look for the problems if you see something isn't right...
Just attach the clip to case ground and power up the radio and touch the tip of the probe to the exposed connector in the header and probe across looking to see which line in that head has power...
Switch to another mode
Repeat, checking each line on that header to see if the bulb lights...
Do this for ALL the modes...
Did you have light on more than one pin of that header?
IF lamp shows inconsistency in brightness, theres' another clue as to where you have problems with power draw.
But this too can help you with the Header and backprobing it...
Get one of these...
Why Bulb? Because of it's non-directional properties. It lets current flow thru both directions. LED are diodes one-way devices - so to check that header, you'll need the one that has that bulb - looks like a lantern type
Now, you'll need it for your Header check...
You'll need to power up the radio for this so you can let the HEADER power the light and show you what does work and what isn't...case ground will be fine for that alligator clip - this is not an insulated chassis radio...
Best results here are to write down your color code to position on the header - for this will help you find out where to look for the problems if you see something isn't right...
Just attach the clip to case ground and power up the radio and touch the tip of the probe to the exposed connector in the header and probe across looking to see which line in that head has power...
Switch to another mode
Repeat, checking each line on that header to see if the bulb lights...
Do this for ALL the modes...
Did you have light on more than one pin of that header?
- Two lines (or more) means you have found an issue with more lines are receiving power - each line should only work for EACH mode only ONE line.
IF lamp shows inconsistency in brightness, theres' another clue as to where you have problems with power draw.
- Dimming or unequal brightness may indicate power being taken from that line to feed others that may not be able to light the lamp but show a power draw keeping parts from (in this case - Switching Transistors) from working right and shunting signal
- or you are sending power into an adjacent line that simply has a soldering problem - meaning that it is past the Diode Matrix and is in close proximity to another circuit you're currently checking (cross feeding)
- Or power ARRIVING to the header and cross feeding into that line from another section - which can cause a transistor to stay on when it shouldn't.
Let's try this again seeing how I could not post the first time.
C78 was checked and replaced when D101 and D102 were checked.
C159 and C41 checked one of the two cant remember was bad.
C97 was bad showed open line. Now as far is my signal generator is conserved it may be fixed. Waiting to hear some one close by talking.
More to come.
Thanks Andy, Kop and Mike
C78 was checked and replaced when D101 and D102 were checked.
C159 and C41 checked one of the two cant remember was bad.
C97 was bad showed open line. Now as far is my signal generator is conserved it may be fixed. Waiting to hear some one close by talking.
More to come.
Thanks Andy, Kop and Mike
- No one is chatting at the moment.
