Re: Schematics?

You have to check it is the right pin out pin 7 and 8 are interchange on the NEC version

Get

Re: Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

Max Donoghue

I've got a couple on order now just in case it turns out to be the issue. Sure would have been nice if they were socketed.?

I'll check those other two test points tonight and report back.

Thank you again for the the help.

Re: Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

#547

开云体育

?

found one for a few quid

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 18 July 2022 17:37
To: Andrew Lenton
Cc: [email protected]
Subject: Re: [YaesuFT847] Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

?

Pin 8 was showing about 4.1V

?

On Mon, Jul 18, 2022 at 12:34 PM Andrew Lenton <a@...> wrote:

Re: Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

Max Donoghue

#546

Correct, it is labelled a "KEY" line in the schematic.

Re: Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

#545

开云体育

Found it

?

Pin 8 is supply

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73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 18 July 2022 17:37
To: Andrew Lenton
Cc: [email protected]
Subject: Re: [YaesuFT847] Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

?

Pin 8 was showing about 4.1V

?

On Mon, Jul 18, 2022 at 12:34 PM Andrew Lenton <a@...> wrote:

REN_P12448EJ3V0DS00_DST_19981101.pdf

Re: Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

#544

开云体育

Hi This is a high gain amp see spec

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73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 18 July 2022 17:37
To: Andrew Lenton
Cc: [email protected]
Subject: Re: [YaesuFT847] Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

?

Pin 8 was showing about 4.1V

?

On Mon, Jul 18, 2022 at 12:34 PM Andrew Lenton <a@...> wrote:

UPC1677_NEC.pdf

Re: Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

Max Donoghue

#543

Pin 8 was showing about 4.1V

Show quoted text

On Mon, Jul 18, 2022 at 12:34 PM Andrew Lenton <a@...> wrote:

Check Pin 8 gets its supply either 5V 8v or 12V or raw 13.8

#542

开云体育

Re: Schematics?

Max Donoghue

#541

Will do, have to check those tonight.

Re: Schematics?

#540

开云体育

Check TP 3009 UHF switch on and VHF switch on TP3010

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 18 July 2022 17:23
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

Hi Andy

On J3005 (VHF) I was getting about 1.4V, on J3006 I was only seeing about 43mV.

These measurements were taking of the output pin (pin 5) of each UPC1677C feeding J3005 and J3006.?

Re: Schematics?

#539

开云体育

Also check TP 3009 below, should go low on TX, it pulls D3035 and D3036 on so the RF signal can pass through

?

73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 18 July 2022 13:44
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

Correct, as crude as it is!

Re: Schematics?

Max Donoghue

#538

Hi Andy

On J3005 (VHF) I was getting about 1.4V, on J3006 I was only seeing about 43mV.

These measurements were taking of the output pin (pin 5) of each UPC1677C feeding J3005 and J3006.?

Re: Schematics?

#537

开云体育

Measure J3005 and J3006 let me know what you get

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 18 July 2022 13:20
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

Comparing the output of Q3002 to Q3007 on the UHF side (both of the RF board) I'm seeing about 1.4V out of Q3002 pin 8, whereas I'm only seeing about 43mv out of Q3007 on pin 8.

I see RF Parts has the UPC1677 in stock, but there is a $15 min order requirement and then $41 to ship. Nuts.

Re: Schematics?

Max Donoghue

#536

Correct, as crude as it is!

Re: Schematics?

#535

Let me check and get back? these voltages are on your RF probe right?

Get

Re: Schematics?

Max Donoghue

#534

Comparing the output of Q3002 to Q3007 on the UHF side (both of the RF board) I'm seeing about 1.4V out of Q3002 pin 8, whereas I'm only seeing about 43mv out of Q3007 on pin 8.

I see RF Parts has the UPC1677 in stock, but there is a $15 min order requirement and then $41 to ship. Nuts.

Re: Schematics?

Max Donoghue

#533

All the adjustments look to be within spec. I had a look at Q3007 (UPC1677C) I compared the readings against Q3011 and I am getting nothing on pin 5 of Q3007. I am getting just over 4V on the KEY line, pin 8.

Perhaps Q3007 is bad. Isn't this the same predriver ICOM used in the 746 and 756 series radios? Lots of them went south. I don't think you can get these anymore.

Max

Re: Schematics?

#532

开云体育

True we can deal with this later

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73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Spence M0STO via groups.io
Sent: 17 July 2022 20:05
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

That’s probably the radio off! 5ppm x 145 on 2m or 725hz and 5ppm x 433mhz for 70cm is 2.165khz.

?

? I would say your radio is in spec in FM.

?

De Spence M0STO?

Sent while portable! please excuse typos.

On 17 Jul 2022, at 19:40, Max Donoghue <ve3tmt@...> wrote:

Hi Andy,

also notice when listening to the local repeaters, the discriminator reading on the meter is off to the left. I actually have to tune about 1.5 KHz above the repeater output if I wanted to center it. Not sure if something is out there either.

Re: Schematics?

#531

开云体育

Hi Ok One thing at a time, let’s look at the low UHF output.

?

If J3006 is low then the fault is not on the RF PA board

?

Go through to 3-2 3-11, it looks like to me something is out of lock or need peaking, you need to get J3006 o/p in the volts! I doubt it is a faulty component

?

The next FT847 I get in for repair I will measure this

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73

?

Andrew

?

Show quoted text

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 17 July 2022 20:19
To: [email protected]
Subject: Re: [YaesuFT847] Schematics?

?

The Yaesu service manual leaves lot to be desired. I can't get I to the service menu with my mic. The fast button is not working.

FT-847 Technical Supplement.pdf

Re: Schematics?

Russ N4MAV

#530

I think he is saying the service manual, not the menu!? There is a big difference there.? The manual, which I put into the files section I think is a much needed thing for the older radios.??

without it, you can't find the problems, nevermind the parts numbers.?
73
Russ, N4MAV