Max Donoghue

J3008 - TX IF ~ 600mV

Checked D3035 and D3036? both 0.762V one way, nothing the other

Max Donoghue

Voltage readings:

J3015 pin 7 (UT8)? 7.83V

J3016 pin 3 (UT8)?? 7.83V

J3011 pin 1 (UHF T8)?? 7.83V

Hi when I need help, a thread like this would have been useful. There has also been endless Emails with regards RS232 interfaces!

Ok I will not reply to the group in the future

73

Andrew

Get

Max Donoghue

#570

Andrew,

Is it possible D3036 is open? If I am getting output on the VHF side, then the TX IF signal must be present at the anode side of D3035 and D3036.

I've verified Q3014 is switching correctly, pulling D3035 low on VHF TX and D3036 low on UHF TX. But what if?D3036 is bad? The TX IF signal would not pass through, correct?

Max

Show quoted text

On Tue, Jul 19, 2022 at 10:58 AM Max Donoghue via <ve3tmt=[email protected]> wrote:

Next up I'll be checking for 8V on TX at the following points:

J3015 pin 7 (UT8)

J3016 pin 3 (UT8)

J3011 pin 1 (UHF T8)

Max Donoghue

#569

Next up I'll be checking for 8V on TX at the following points:

J3015 pin 7 (UT8)

J3016 pin 3 (UT8)

J3011 pin 1 (UHF T8)

#568

The opening line to the opening page is

"This site exists for the exchange of ideas, advice, technical and general information for the Yaesu Transceiver known as the FT-847."

I would suggest if you find the QRM not to your taste, just spin the dial.?

Max Donoghue

#567

Also checked these voltages and all were good

#566

开云体育

Hi All,

Fantastic thread, have been following every exchange, looking forward to the result. Have a non Modded FT847 good luck guys?

‘73

Paul?

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On 19 Jul 2022, at 13:26, Andy Bosworth <sidthepop@...> wrote:

?
I see no reason why it should be off line. A worthwhile exercise in fault finding,

Virus-free.

On Tue, 19 Jul 2022 at 13:21, Max Donoghue <ve3tmt@...> wrote:

Not a problem Ian. I thought others would benefit from the exercise. Sorry to have bothered the group.

I'll continue the repair through private messaging.

If any other members might be interested in the final result I'll post a follow up when repaired.

Ian

#565

Your choice....QRM is optional.

Show quoted text

On Tue, Jul 19, 2022, at 20:25, Andy Bosworth wrote:

I see no reason why it should be off line. A worthwhile exercise in fault finding,

Virus-free.

On Tue, 19 Jul 2022 at 13:21, Max Donoghue <ve3tmt@...> wrote:
Not a problem Ian. I thought others would benefit from the exercise. Sorry to have bothered the group.

I'll continue the repair through private messaging.

If any other members might be interested in the final result I'll post a follow up when repaired.

#564

I see no reason why it should be off line. A worthwhile exercise in fault finding,

Virus-free.

Show quoted text

On Tue, 19 Jul 2022 at 13:21, Max Donoghue <ve3tmt@...> wrote:

Not a problem Ian. I thought others would benefit from the exercise. Sorry to have bothered the group.

I'll continue the repair through private messaging.

If any other members might be interested in the final result I'll post a follow up when repaired.

Ian

#563

That's great Max, I hope it reaches a resolution.

Show quoted text

On Tue, Jul 19, 2022, at 20:21, Max Donoghue wrote:

Not a problem Ian. I thought others would benefit from the exercise. Sorry to have bothered the group.

I'll continue the repair through private messaging.

If any other members might be interested in the final result I'll post a follow up when repaired.

Max Donoghue

#562

Not a problem Ian. I thought others would benefit from the exercise. Sorry to have bothered the group.

I'll continue the repair through private messaging.

If any other members might be interested in the final result I'll post a follow up when repaired.

Ian

#561

This is a bit like a "death by a thousand cuts". Any chance you could go off-line?

Show quoted text

On Tue, Jul 19, 2022, at 19:36, Andrew Lenton wrote:

In that case Q3007 is fine, you need to trace back and find your signal from the RF board, it will be an UHF osc out of luck! Is my guess or a LO to mix up to UHF let me study further
?
73
?
Andrew
?
?
From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 19 July 2022 12:17
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?
?
On Q3011 (VHF) I get 313mV on pin 1, 1.4V on pin 5

On Q3007 (UHF) nothing on either pin 1 or 5
?

#560

开云体育

In that case Q3007 is fine, you need to trace back and find your signal from the RF board, it will be an UHF osc out of luck! Is my guess or a LO to mix up to UHF let me study further

?

73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 19 July 2022 12:17
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

On Q3011 (VHF) I get 313mV on pin 1, 1.4V on pin 5

On Q3007 (UHF) nothing on either pin 1 or 5

?

Max Donoghue

#559

On Q3011 (VHF) I get 313mV on pin 1, 1.4V on pin 5

On Q3007 (UHF) nothing on either pin 1 or 5

#558

开云体育

Phew, have you checked the I/P pin 1, and compared it with Pin 1 on the VHF side, I am guessing they should be similar!

?

73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 19 July 2022 11:48
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

Hi Andy,

Sorry meant Q3011.

Max Donoghue

#557

Hi Andy,

Sorry meant Q3011.

#556

开云体育

Hi do you mean: Q3007? What is pin 1 of the UPC1677Cs’

?

I have not found Q3006!

?

73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 19 July 2022 11:04
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

Based on the comparison reasons against its VHF counterpart, I still think Q3007 is bad. I have a couple on the way but won't be here for a week or so.

Max Donoghue

#555

Based on the comparison reasons against its VHF counterpart, I still think Q3007 is bad. I have a couple on the way but won't be here for a week or so.

#554

That is good news

Get