Sony KV2000 HF1A diode - UK Vintage Radio Repair and Restoration Discussion Forum

simpsons · 25th Feb 2023, 7:03 pm

The power supply excess current protection failed when the SG613 short circuit after the set had been running for 30mins.

The Sony fault guide advises that the cause is D808 a Sony Part HF1A going open circuit when hot.

I am told that it will take 4 weeks for a replacement, and I wonder if there is a equivalent?

To add insult to injury, the failure of the ECP took the HT regulator 2SC1413 with it. Is there a test for the ECP which doesn't destroy the HT regulator?

Chris

simpsons · 28th Feb 2023, 12:17 pm

After going around in circles, including finding an RCA equivalent diode only available from Uncle Sam, from a simple search, Sony recommend a replacement part # GH3F.

Donberg recommend the equivalent BY228 which I have ordered.

Why it took me so long to find the answer goodness only knows!!

Chris

Maarten · 28th Feb 2023, 6:41 pm

The specs of the diode seem hard to find. The go to modern replacement for similar types is the UF4007, but that one is only 1000V 1A so not suitable for all TV applications. The BY228 is quite a bit slower but can handle 3A. I think that's a safe choice.

simpsons · 28th Feb 2023, 8:46 pm

Thank you Maarten for your comments.

I did consider the BY448 but looking at the specification, recommendation and availability, the BY228 was chosen.

Chris

Philips210 · 28th Feb 2023, 10:06 pm

Chris, you probably already know but there was a good servicing article in Television magazine on the KV2000. It was in Aug/Sep 1984 issues.

In my ECA data books, for the GH3F diode a BY228 or BY448 is listed as an equivalent.

I couldn't find the HF1A diode listed. This may be a red herring though but I found type HFSD-1A listed. I wonder if the SD part relates to Sony Diode? For that a BA159 is listed as an equivalent.

Regards,
Symon

simpsons · 1st Mar 2023, 10:49 am

Hi Symon

I do have Television guide which, together with the fault list in Obsolete Technology Tellye, gave me a list of what could go wrong.

Unfortunately because the Excess Current circuit didn't kick in, after I replaced the power supply regulator, the advice that to fault find I start by removing F4 lead to the audio section was wrong. I should have begun with the Horizontal Timebase.

The horizontal output SG613 was short circuit between the gates, and so a new 2SC1413 regulator also "bit the dust." The thump I heard when the TV was switched on rang alarm bells, but too late

Whilst the 3amp fuse in the plug blew, the 3.15 amp fuse on the power supply board didn't.

So, I'm going to tread very carefully with fault location and hopefully, by bringing the set up by a variac, the last 2SC1413 I have will survive.

Fortunately, some time ago, I bought 3 off SG613's and so I'm ok there.

Chris

25th Feb 2023, 7:03 pm	#1
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Sony KV2000 HF1A diode The power supply excess current protection failed when the SG613 short circuit after the set had been running for 30mins. The Sony fault guide advises that the cause is D808 a Sony Part HF1A going open circuit when hot. I am told that it will take 4 weeks for a replacement, and I wonder if there is a equivalent? To add insult to injury, the failure of the ECP took the HT regulator 2SC1413 with it. Is there a test for the ECP which doesn't destroy the HT regulator? Chris

28th Feb 2023, 12:17 pm	#2
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Re: Sony KV2000 HF1A diode After going around in circles, including finding an RCA equivalent diode only available from Uncle Sam, from a simple search, Sony recommend a replacement part # GH3F. Donberg recommend the equivalent BY228 which I have ordered. Why it took me so long to find the answer goodness only knows!! Chris

28th Feb 2023, 6:41 pm	#3
Maarten Dekatron Join Date: Dec 2007 Location: Haarlem, Netherlands Posts: 4,203	Re: Sony KV2000 HF1A diode The specs of the diode seem hard to find. The go to modern replacement for similar types is the UF4007, but that one is only 1000V 1A so not suitable for all TV applications. The BY228 is quite a bit slower but can handle 3A. I think that's a safe choice.

28th Feb 2023, 8:46 pm	#4
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Re: Sony KV2000 HF1A diode Thank you Maarten for your comments. I did consider the BY448 but looking at the specification, recommendation and availability, the BY228 was chosen. Chris

28th Feb 2023, 10:06 pm	#5
Philips210 Nonode Join Date: May 2007 Location: Redruth, Cornwall, UK. Posts: 2,579	Re: Sony KV2000 HF1A diode Chris, you probably already know but there was a good servicing article in Television magazine on the KV2000. It was in Aug/Sep 1984 issues. In my ECA data books, for the GH3F diode a BY228 or BY448 is listed as an equivalent. I couldn't find the HF1A diode listed. This may be a red herring though but I found type HFSD-1A listed. I wonder if the SD part relates to Sony Diode? For that a BA159 is listed as an equivalent. Regards, Symon

1st Mar 2023, 10:49 am	#6
simpsons Octode Join Date: Feb 2007 Location: Harrow, London, UK. Posts: 1,493	Re: Sony KV2000 HF1A diode Hi Symon I do have Television guide which, together with the fault list in Obsolete Technology Tellye, gave me a list of what could go wrong. Unfortunately because the Excess Current circuit didn't kick in, after I replaced the power supply regulator, the advice that to fault find I start by removing F4 lead to the audio section was wrong. I should have begun with the Horizontal Timebase. The horizontal output SG613 was short circuit between the gates, and so a new 2SC1413 regulator also "bit the dust." The thump I heard when the TV was switched on rang alarm bells, but too late Whilst the 3amp fuse in the plug blew, the 3.15 amp fuse on the power supply board didn't. So, I'm going to tread very carefully with fault location and hopefully, by bringing the set up by a variac, the last 2SC1413 I have will survive. Fortunately, some time ago, I bought 3 off SG613's and so I'm ok there. Chris