Recommend you measure right across the rectifier outputs, don't trust your ground. It's usually a good idea to float the ground of your power cord when using a scope to measure across two points when one isn't earth ground, either with a ground adapter or by removing the ground pin from the power cord. -----Original Message----- From: firstname.lastname@example.org [mailto:email@example.com] On Behalf Of firstname.lastname@example.org Sent: Friday, August 07, 2009 9:30 AM To: email@example.com Subject: RE: Dead PET 2001 Hallo Phil, Just out of my head: the 8VAC should be rectified and supply the power for the 7805s. Instead you read 0V. My conclusion: - dead rectifiers (BOTH are brooken ???) - bad connection So do me a favour and measure directly on the outputs of the diodes. -- ___ / __|__ / / |_/ Groetjes, Ruud \ \__|_\ \___| URL: Ruud.C64.org Bugs in my programs? Probably a lot, but none I am aware of. -----Oorspronkelijk bericht----- Van: firstname.lastname@example.org [mailto:email@example.com] Namens Philip Lord Verzonden: vrijdag 7 augustus 2009 14:26 Aan: firstname.lastname@example.org Onderwerp: Re: Dead PET 2001 Hi again, Sorry it took me so long to get around to measuring the voltages off my machine...I hope you are all still here. So here we go (All voltages are approximates): Between the two transformer tabs that go to the monitor - 16VAC Pin1 - 8VAC Pin2 - 0V Pin4 - 0V Pin5 - 8VAC I also took measurements on the 7805's and as they are tied to pin2, there is no voltage read. 0V. Pin2 and Pin4 both come from the same place off the huge blue capacitor, so maybe I can assume this is dead? Is there anyway to test this capacitor? Any further advice would be greatly appreciated. Thanks again Phil On Jul 30, 2009, at 11:50 AM, Ethan Dicks wrote: > On Wed, Jul 29, 2009 at 10:39 PM, William > Levak<email@example.com > > wrote: >> I pulled out my 2001 and took some measurememts. On connector J8 the >> center wire is ground. Measuring from the various pins to ground. >> >> Pin 1 - 8V >> pin 2 - 20V >> pin 4 - 20V >> pin 5 - 8V >> >> Measuring between the two wires on the transformer that go to the >> video board - 16V. > > That all makes sense - 8V should be enough headroom for a 7805 and > ISTR there's a 7812 on the monitor analog board, so 16V is plenty hot > enough to get 12V from a 7812 (+15V happens to be enough). > > -ethan > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing list De informatie in dit e-mailbericht is vertrouwelijk en uitsluitend bestemd voor de geadresseerde. Wanneer u dit bericht per abuis ontvangt, verzoeken wij u contact op te nemen met de afzender per kerende e-mail. Verder verzoeken wij u in dat geval dit e-mailbericht te vernietigen en de inhoud ervan aan niemand openbaar te maken. Wij aanvaarden geen aansprakelijkheid voor onjuiste, onvolledige dan wel ontijdige overbrenging van de inhoud van een verzonden e-mailbericht, noch voor daarbij overgebrachte virussen. APG Algemene Pensioen Groep NV is gevestigd te Heerlen en is ingeschreven in het handelsregister van de Kamer van Koophandel Limburg onder nummer 14099617 The information contained in this e-mail is confidential and may be privileged. It may be read, copied and used only by the intended recipient. If you have received it in error, please contact the sender immediately by return e-mail; please delete in this case the e-mail and do not disclose it's contents to any person. We don't accept liability for any errors, omissions, delays of receipt or viruses in the contents of this message which arise as a result of e-mail transmission. APG Algemene Pensioen Groep NV is registered in the trade register of the Chamber of Commerce Limburg, The Netherlands, registration number: 14099617 Message was sent through the cbm-hackers mailing list -- This message has been scanned for viruses and dangerous content by IDSi's MailScanner. Message was sent through the cbm-hackers mailing listReceived on 2009-08-07 16:23:41
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