Re: IBM 5110 transformer?
Really good point. Thanks! I will check with my friend. /Mattis Den mån 30 sep. 2019 kl 16:46 skrev Paul Berger via cctalk < cctalk@classiccmp.org>: > > On 2019-09-30 3:44 a.m., Mattis Lind via cctalk wrote: > > A friend of mine is trying to repair a IBM 5110. He is convinced that the > > transformer is bad. > > > > Anyone knows the spec of the transformer? > > > > Someone that has a spare? > > > > Looking into the tech documentation tell me that the machine requires +/- > > 5V and +/- 12 V and also +8.5V > > > > A very rough guesstimate based on the number of wires from the PSU to the > > backplane would give 20A 5V, 4A +12V, 4A +8.5V, 1A -5V and 1A -12V. > > > > Anyone with a better guess? > > > > /Mattis > > Does this transformer has a resonant capacitor on it? They where very > common on IBM power supplies from that time period and if the capacitor > goes short you will not get any output from the transformer. This is a > lesson I learned as a green service rep 40 years ago after lugging in a > very heavy transformer for a machine. > > Paul. > >
Re: IBM 5110 transformer?
On 2019-09-30 3:44 a.m., Mattis Lind via cctalk wrote: A friend of mine is trying to repair a IBM 5110. He is convinced that the transformer is bad. Anyone knows the spec of the transformer? Someone that has a spare? Looking into the tech documentation tell me that the machine requires +/- 5V and +/- 12 V and also +8.5V A very rough guesstimate based on the number of wires from the PSU to the backplane would give 20A 5V, 4A +12V, 4A +8.5V, 1A -5V and 1A -12V. Anyone with a better guess? /Mattis Does this transformer has a resonant capacitor on it? They where very common on IBM power supplies from that time period and if the capacitor goes short you will not get any output from the transformer. This is a lesson I learned as a green service rep 40 years ago after lugging in a very heavy transformer for a machine. Paul.
Re: IBM 5110 transformer?
Den mån 30 sep. 2019 kl 15:37 skrev dwight : > Is it a switcher or an AC? > Good old transfomer. He could probably find something suitable if the specs were known. Or replace it with switchers at least for testing the machine. But still it would be great to know the specs. > A custom transformer is going to be quite expensive. About the only way is > to cannibalize another machine. > Dwight > /Mattis > > -- > *From:* cctalk on behalf of Mattis Lind > via cctalk > *Sent:* Sunday, September 29, 2019 11:44 PM > *To:* General Discussion: On-Topic and Off-Topic Posts < > cctalk@classiccmp.org> > *Subject:* IBM 5110 transformer? > > A friend of mine is trying to repair a IBM 5110. He is convinced that the > transformer is bad. > > Anyone knows the spec of the transformer? > > Someone that has a spare? > > Looking into the tech documentation tell me that the machine requires +/- > 5V and +/- 12 V and also +8.5V > > A very rough guesstimate based on the number of wires from the PSU to the > backplane would give 20A 5V, 4A +12V, 4A +8.5V, 1A -5V and 1A -12V. > > Anyone with a better guess? > > /Mattis >
Re: IBM 5110 transformer?
Is it a switcher or an AC? A custom transformer is going to be quite expensive. About the only way is to cannibalize another machine. Dwight From: cctalk on behalf of Mattis Lind via cctalk Sent: Sunday, September 29, 2019 11:44 PM To: General Discussion: On-Topic and Off-Topic Posts Subject: IBM 5110 transformer? A friend of mine is trying to repair a IBM 5110. He is convinced that the transformer is bad. Anyone knows the spec of the transformer? Someone that has a spare? Looking into the tech documentation tell me that the machine requires +/- 5V and +/- 12 V and also +8.5V A very rough guesstimate based on the number of wires from the PSU to the backplane would give 20A 5V, 4A +12V, 4A +8.5V, 1A -5V and 1A -12V. Anyone with a better guess? /Mattis
IBM 5110 transformer?
A friend of mine is trying to repair a IBM 5110. He is convinced that the transformer is bad. Anyone knows the spec of the transformer? Someone that has a spare? Looking into the tech documentation tell me that the machine requires +/- 5V and +/- 12 V and also +8.5V A very rough guesstimate based on the number of wires from the PSU to the backplane would give 20A 5V, 4A +12V, 4A +8.5V, 1A -5V and 1A -12V. Anyone with a better guess? /Mattis
