Re: Intermittent Loss of Pre-Driver signal
Hi Steve It is not conclusive that they are connected from that data sheet. It may be that the tag is for heat transfer only and in this case is soldered to ground merely for that reason. If you could resolver that pin as well that could be the answer. When you said the voltages are consistent at the device, it really points to the device really doesn’t it? If the voltages varied it would point to a resistor/inductor on those voltage lines. I know it would be difficult to do, but if you could clear the solder away from all pins with solder wick and then reflow.
I await results when replacement device fitted. Best of luck with that. 73 Neil
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On 27 Nov 2024, at 3:17?AM, Steve G4ALG <steve@...> wrote:
? Hi Neil
?
Thank you, again.
The DC conditions on the gate and drain are consistently OK - regardless of whether the fault is present.?
> Were you thinking that the tag was poorly soldered perhaps?
With the FET still on the board, both the source and the tab are soldered directly to ground.? The reason I want to know whether the source and tab are connected internally is this:? From the side of the transceiver, I have been able to apply the soldering iron, and a little more flux and solder, to the drain and gate (the outermost terminals), and to the tab.? ?Applying the soldering iron (from the side) to the centre (source) terminal will be more difficult at this low angle of attack.? ?If the tab is internally connected to the source, I am happy that there is a good enough ground to the source.? If the tab is not internally connected to the source, I might be tempted to try to the re-solder the source terminal.??
I'll take a photo soon.?
I have ordered a replacement transistor for Q102.
More later . . . .
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Re: Intermittent Loss of Pre-Driver signal
Hi Neil
?
Thank you, again.
The DC conditions on the gate and drain are consistently OK - regardless of whether the fault is present.?
> Were you thinking that the tag was poorly soldered perhaps?
With the FET still on the board, both the source and the tab are soldered directly to ground.? The reason I want to know whether the source and tab are connected internally is this:? From the side of the transceiver, I have been able to apply the soldering iron, and a little more flux and solder, to the drain and gate (the outermost terminals), and to the tab.? ?Applying the soldering iron (from the side) to the centre (source) terminal will be more difficult at this low angle of attack.? ?If the tab is internally connected to the source, I am happy that there is a good enough ground to the source.? If the tab is not internally connected to the source, I might be tempted to try to the re-solder the source terminal.??
I'll take a photo soon.?
I have ordered a replacement transistor for Q102.
More later . . . .
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Re: Intermittent Loss of Pre-Driver signal
Hi Steve I have had a look in the manual at the board, there are resistors on underside and mostly RF path on topside from what I can see. Can you indicate where you are putting pressure on the board, and how much.
It looks like the middle pin is also the tag, just by the way Q101 and Q102 are placed on board.. Were you thinking that the tag was poorly soldered perhaps? 73 Neil
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On 27 Nov 2024, at 12:04?AM, Neil Lintott via groups.io <nl3adc@...> wrote:
? Hi Steve There are 2 voltages 2.81V and 8V mentioned on circuit diagram. The 2.81V appears as a voltage divider and feeds gate through a resistor and the 8V appears at drain through a couple of resistors. Is it possible to measure these while pressing on board to see if they change during fault condition.? As for question re tab of the driver device, it is not mentioned in data sheet if connected nor in picture. With the radio off you could try doing an ohms measurement between the tab and the 3 pins to see if any are connected. Try applying the pressure during this check as well if possible. Are you able to take a closeup photo of this area of the board to show us please. Hope this is of some help.
73 Neil On 26 Nov 2024, at 9:12?PM, Steve G4ALG <steve@...> wrote:
? Neil ZL3ADC: Thank you.? I'll do the fan modification once the rig is working again.
To All:
Regarding the pre-driver device Q102, RD01MUS1.? ?This device seems to be most sensitive to tweaks of the PCB, but I have been unable to positively isolate the fault to Q102 with it still being soldered to the PCB.?
It would be helpful to know whether the device's Source connection is internally bonded to the Tab connection.? ?Both get soldered to ground on the PA Unit board.? ? I have found a data sheet at:
But it is not clear to me how to use the data sheet to ascertain whether the Source is internally connected to the Tab.? ?I would appreciate some help on this point.? Of course, if you have a RD01MUS1 on hand, I'd appreciate your observations with a test meter!
73
Steve G4ALG
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Re: Intermittent Loss of Pre-Driver signal
Hi Steve There are 2 voltages 2.81V and 8V mentioned on circuit diagram. The 2.81V appears as a voltage divider and feeds gate through a resistor and the 8V appears at drain through a couple of resistors. Is it possible to measure these while pressing on board to see if they change during fault condition.? As for question re tab of the driver device, it is not mentioned in data sheet if connected nor in picture. With the radio off you could try doing an ohms measurement between the tab and the 3 pins to see if any are connected. Try applying the pressure during this check as well if possible. Are you able to take a closeup photo of this area of the board to show us please. Hope this is of some help.
73 Neil
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On 26 Nov 2024, at 9:12?PM, Steve G4ALG <steve@...> wrote:
? Neil ZL3ADC: Thank you.? I'll do the fan modification once the rig is working again.
To All:
Regarding the pre-driver device Q102, RD01MUS1.? ?This device seems to be most sensitive to tweaks of the PCB, but I have been unable to positively isolate the fault to Q102 with it still being soldered to the PCB.?
It would be helpful to know whether the device's Source connection is internally bonded to the Tab connection.? ?Both get soldered to ground on the PA Unit board.? ? I have found a data sheet at:
But it is not clear to me how to use the data sheet to ascertain whether the Source is internally connected to the Tab.? ?I would appreciate some help on this point.? Of course, if you have a RD01MUS1 on hand, I'd appreciate your observations with a test meter!
73
Steve G4ALG
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Re: Intermittent Loss of Pre-Driver signal
Neil ZL3ADC: Thank you.? I'll do the fan modification once the rig is working again.
To All:
Regarding the pre-driver device Q102, RD01MUS1.? ?This device seems to be most sensitive to tweaks of the PCB, but I have been unable to positively isolate the fault to Q102 with it still being soldered to the PCB.?
It would be helpful to know whether the device's Source connection is internally bonded to the Tab connection.? ?Both get soldered to ground on the PA Unit board.? ? I have found a data sheet at:
But it is not clear to me how to use the data sheet to ascertain whether the Source is internally connected to the Tab.? ?I would appreciate some help on this point.? Of course, if you have a RD01MUS1 on hand, I'd appreciate your observations with a test meter!
73
Steve G4ALG
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Re: Intermittent Loss of Pre-Driver signal
Hi Steve Yes plated through holes could also be an issue, I have seen where a track has cracked very close to donut on one side of plated through hole, very hard to see. I have also seen plated through hole holes where the graphite in the hole has not held the plating well. This can normally be fixed if there is room in hole by pushing a thin strand of tinned copper wire through the hole and soldering to tracks on both sides.
Hop this helps also. 73
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On 25 Nov 2024, at 9:34?AM, Neil Lintott via groups.io <nl3adc@...> wrote:
? Hi Steve There are two fan mods.this is the one I did.
Contact author: M3SVO?
!! IF YOU ARE UNSURE ABOUT PERFORMING THIS MOD DON’T!!?
!!IF YOU DAMAGE YOUR RADIO YOU ONLY HAVE YOURSELF TO BLAME!!?
I have performed this mod on MY OWN radio without any adverse affects and my LDG AT-7000 atu still works as it should.?
Before this mod after been turned on for an hour or so the temp meter on the radio would show around 50% on the scale (7 or 8 bars), after the mod the temp meter shows around 25% on the scale (4 bars).?
First remove the top cover and remove the fan from the radio,?
take a 100ohm resistor and solder a length of wire to each end and cover with heat shrink tubing. Cut the red wire to the fan and attach one of the resistor wires between the two halves and cover with heat shrink tubing.?
Next follow the ORANGE wire from the ATU molex socket on the back of the radio to where it is soldered on to the DDS unit (top right hand corner at the back of the radio) and attach the remaining resistor wire to this point, position the resistor and wires so that they look neat and tidy and then refit the fan and the top cover, mod is now complete.
If you google IC7000 Fan Mod you will find other/s and other mods that have. Been done.
I have had no troubles with mine approx 12 years old now. Only issue is the mic cord split, which I have taped up with self amalgamating rubber tape in meantime.
73 Neil
On 25 Nov 2024, at 9:14?AM, Steve G4ALG <steve@...> wrote:
? Hi Neal
?
I'm very grateful to you for your thoughts.? ?I have never used freeze spray, but I have heard good things about it when used for investigating intermittent faults.? I have now ordered a 600 ml can!? ?Old dog, new tricks.
?
Yes, all the soldered joints look wonderful.? But I guess that we've both been surprised by discovering a faulty joint that looked perfect from the outside.? I'm also wondering about the plated-through holes being another possible source of trouble.??
I'll update this thread when I have news.
If you have a reference for the fan modification, I'd be grateful if you could send it to me.
?
73
Steve G4ALG
?
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Re: Intermittent Loss of Pre-Driver signal
Hi Steve There are two fan mods.this is the one I did.
Contact author: M3SVO?
!! IF YOU ARE UNSURE ABOUT PERFORMING THIS MOD DON’T!!?
!!IF YOU DAMAGE YOUR RADIO YOU ONLY HAVE YOURSELF TO BLAME!!?
I have performed this mod on MY OWN radio without any adverse affects and my LDG AT-7000 atu still works as it should.?
Before this mod after been turned on for an hour or so the temp meter on the radio would show around 50% on the scale (7 or 8 bars), after the mod the temp meter shows around 25% on the scale (4 bars).?
First remove the top cover and remove the fan from the radio,?
take a 100ohm resistor and solder a length of wire to each end and cover with heat shrink tubing. Cut the red wire to the fan and attach one of the resistor wires between the two halves and cover with heat shrink tubing.?
Next follow the ORANGE wire from the ATU molex socket on the back of the radio to where it is soldered on to the DDS unit (top right hand corner at the back of the radio) and attach the remaining resistor wire to this point, position the resistor and wires so that they look neat and tidy and then refit the fan and the top cover, mod is now complete.
If you google IC7000 Fan Mod you will find other/s and other mods that have. Been done.
I have had no troubles with mine approx 12 years old now. Only issue is the mic cord split, which I have taped up with self amalgamating rubber tape in meantime.
73 Neil
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On 25 Nov 2024, at 9:14?AM, Steve G4ALG <steve@...> wrote:
? Hi Neal
?
I'm very grateful to you for your thoughts.? ?I have never used freeze spray, but I have heard good things about it when used for investigating intermittent faults.? I have now ordered a 600 ml can!? ?Old dog, new tricks.
?
Yes, all the soldered joints look wonderful.? But I guess that we've both been surprised by discovering a faulty joint that looked perfect from the outside.? I'm also wondering about the plated-through holes being another possible source of trouble.??
I'll update this thread when I have news.
If you have a reference for the fan modification, I'd be grateful if you could send it to me.
?
73
Steve G4ALG
?
|
Re: Intermittent Loss of Pre-Driver signal
Hi Neal
?
I'm very grateful to you for your thoughts.? ?I have never used freeze spray, but I have heard good things about it when used for investigating intermittent faults.? I have now ordered a 600 ml can!? ?Old dog, new tricks.
?
Yes, all the soldered joints look wonderful.? But I guess that we've both been surprised by discovering a faulty joint that looked perfect from the outside.? I'm also wondering about the plated-through holes being another possible source of trouble.??
I'll update this thread when I have news.
If you have a reference for the fan modification, I'd be grateful if you could send it to me.
?
73
Steve G4ALG
?
|
Re: Intermittent Loss of Pre-Driver signal
Hi Steve I have not seen this fault personally. I am an ex radio technician of many years. And I own a IC7000 myself. From what you have described, I suggest the fault is more likely physical than electronic. Pressure on board would indicate to me a dry joint, or a hair line crack in a track or similar. The pressure could be moving a solder joint that looks OK visually, but has oxidized internally and only needs a bit of movement to make contact. One method to isolate, would be a can of freeze, spraying a small amount on tracks. Personally I would do a close visual inspection under bright light, even shining through board if necessary.? I have not had the covers off mine except to do fan mod, as it used to run very hot, that was cured by fan mod. Hope this is of some use in meantime. 73’蝉
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On 25 Nov 2024, at 3:23?AM, Steve G4ALG <steve@...> wrote:
? IC-7000: Intermittent Loss of Pre-Driver signal
I've owned my IC-7000 for about three weeks, and it's now got an intermittent transmit fault affecting all bands.
The fault can be made to come and go when using the back of a small screwdriver to gently impact the PA Unit board in the pre-driver area of the board.? ? When the fault is on, I have TX signal at the gate of Q102, but no signal (or variable signal) at its drain.? ?The DC conditions on the gate and drain are consistently OK - regardless of whether the fault is present.? ?The TX signal at the drain of Q102 is highly variable between the fully working and fully non-working states.
Note:
All my measurements are being made at the components that I have access to from the bottom view of the PA Unit board.? ?To this extent, I must admit that I'm not making measurements directly on the pins of Q102 itself.
I'm currently attempting to isolate the fault, but do not know whether I'm looking for an intermittent open circuit condition, or an AC shunt path from the drain of Q102 to ground.
Has anyone here resolved a similar fault?? ? ?All tips gratefully appreciated.
With best wishes
Steve G4ALG
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Intermittent Loss of Pre-Driver signal
IC-7000: Intermittent Loss of Pre-Driver signal
I've owned my IC-7000 for about three weeks, and it's now got an intermittent transmit fault affecting all bands.
The fault can be made to come and go when using the back of a small screwdriver to gently impact the PA Unit board in the pre-driver area of the board.? ? When the fault is on, I have TX signal at the gate of Q102, but no signal (or variable signal) at its drain.? ?The DC conditions on the gate and drain are consistently OK - regardless of whether the fault is present.? ?The TX signal at the drain of Q102 is highly variable between the fully working and fully non-working states.
Note:
All my measurements are being made at the components that I have access to from the bottom view of the PA Unit board.? ?To this extent, I must admit that I'm not making measurements directly on the pins of Q102 itself.
I'm currently attempting to isolate the fault, but do not know whether I'm looking for an intermittent open circuit condition, or an AC shunt path from the drain of Q102 to ground.
Has anyone here resolved a similar fault?? ? ?All tips gratefully appreciated.
With best wishes
Steve G4ALG
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IC-7000 with separation kit for sale
My IC-7000 is for sale. Includes new separation kit. Please email kc9c at yahoo for more information.
?
Mark KC9C
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Interesting question, could anyone find information about the values ??of the IC-7000 Main Board L701 Transformer, the coil itself can't be found anywhere, so you have to do it if you don't happen to find something used.
T. Pentti OH5KOA
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Re: IC-7000 no rx and no sound out from speaker
Hi Geoff
While I wait for the parts to come in I thought to apply the recommended mods?
Also the pre driver transistor heat issue seems to be another issue with this radio
James?
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Re: IC-7000 no rx and no sound out from speaker
These cables are often handled inappropriately and the connecting end can lift the track
When pushed incorrectly into the pcb connector.
Yes, I would add the gate resistor for sure. It's seems to be hit and miss if these driver boards burn up. I had one that had worked fine for 10 years before it destroyed itself.
Geoff
On Thu, 14 Nov 2024, 10:04 James Tiberius via , <nono2212000= [email protected]> wrote: Hi Geoff
yes they are in a bad state - found bent contact strips on all cables. these cables are pretty weak and not well made.
I decided to pull the unit apart to check the driver board which is the original and from what i have been reading is prone to oscillation - do you think its worth while modifying with the resistor to prevent the oscillation occurring?
james
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Re: IC-7000 no rx and no sound out from speaker
Hi Geoff
yes they are in a bad state - found bent contact strips on all cables. these cables are pretty weak and not well made.
I decided to pull the unit apart to check the driver board which is the original and from what i have been reading is prone to oscillation - do you think its worth while modifying with the resistor to prevent the oscillation occurring?
james
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Re: shut down / restart on keying, now no power
Save the old, bad one. I’ll bet the connection was broken where you had the photo. Should be an easy fix and you have a spare.?
Tage
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On Nov 13, 2024, at 10:27, Tage Carlson via groups.io <tage_carlson@...> wrote:
?
Congratulations.
Hello all,?
?
Problem solved. I replaced the power supply cables and rig powered on.
?
Thanks for all your help!
?
73,
Colin N2TQT
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Re: shut down / restart on keying, now no power
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Hello all,?
?
Problem solved. I replaced the power supply cables and rig powered on.
?
Thanks for all your help!
?
73,
Colin N2TQT
|
Re: shut down / restart on keying, now no power
Hello all,?
?
Problem solved. I replaced the power supply cables and rig powered on.
?
Thanks for all your help!
?
73,
Colin N2TQT
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Re: IC-7000 no rx and no sound out from speaker
Good move. These cables can produce weird faults if they are handled poorly. Make sure the small backup strip is in place on the new cables.
Looks like someone has been inside this radio then!
On Wed, 13 Nov 2024, 15:12 James Tiberius via , <nono2212000= [email protected]> wrote: Just an update-
still waiting for IC551 to arrive.
I had a look at the ribbon cables and they are not in the best condition so I ordered a new set from icom today - 60aud for 5 cables including gst and postage
james
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Re: IC-7000 no rx and no sound out from speaker
Just an update-
still waiting for IC551 to arrive.
I had a look at the ribbon cables and they are not in the best condition so I ordered a new set from icom today - 60aud for 5 cables including gst and postage
james
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Steve G4ALG