WTBorrow Isolation Transformer, Variac, Central Connecticut US - Page 1
Forum section: electronics / general

author: JonHendry
author_rank: Contributor
timestamp: September 07, 2018, 12:46:51 am
content: EDIT/UPDATE: I've ordered a cheap chinesium variac via EBay and placed a bid on a bare 1962 isolation transformer which the seller describes as having been used for protection while working on electronics, so I hopefully won't be needing to borrow anything.I'm going to be refurbishing an old 1950s reel to reel tape deck, so I can transfer some old tapes my late father made to digital.I'd like to do it the safe way but I don't have the cash right now for a variac and isolation transformer.If anyone has some I could borrow, that'd be great. I'd be willing to provide collateral in the form of a 68040 NeXTStation computer (no monitor, RAM, or hard drive, but still worth several hundred dollars due to the rarity and collector value.)I'm in Connecticut in the area of I-691.

author: philipz
author_rank: Contributor
timestamp: September 08, 2018, 08:02:49 am
content: Only want to remind you that this variac maybeNOT ISOLATED. If you have a work in hi side of power supply bevery careful!

author: edavid
author_rank: Super Contributor
timestamp: September 08, 2018, 06:54:58 pm
content: I don't see why you would need either one to service a tape deck

author: philipz
author_rank: Contributor
timestamp: September 15, 2018, 01:48:38 pm
content: Quote from: edavid on September 08, 2018, 06:54:58 pmBecause time make oil and grease solid substances

author: edavid
author_rank: Super Contributor
timestamp: September 15, 2018, 01:59:00 pm
content: Quote from: philipz on September 15, 2018, 01:48:38 pmHow is a variac going to help you remove oil and grease

author: philipz
author_rank: Contributor
timestamp: September 15, 2018, 02:10:56 pm
content: Quote from: edavid on September 15, 2018, 01:59:00 pmYour question was: why you would need either one to service a tape deckI saw some old (very old) tape deck with non isolated part of power supply driven directly from mains, especially motors. Maybe JonHendry actually need isolation transformer, but he can explain better.

author: JugglingElectrons
author_rank: Contributor
timestamp: September 23, 2018, 06:10:53 am
content: Do you guys know if there are any places to get some cheap complete isolation transformers online other than places like eBay? I've been lucky to snag some Variacs/Variable Autotransformers at some local auctions but haven't seen just a 1:1 isolation transformer with female banana jacks or an outlet. Haven't checked online in awhile but didn't know if there are any decent modern manufacturers.Is this something to consider doing as a DIY projects by either winding my own transformer or just putting an assembled one in a box? I feel like tons of the Variacs and isolation transformers I see were custom made back in the 80s and 90s sometimes even as far back as the 60s.

author: PlainName
author_rank: Super Contributor
timestamp: September 23, 2018, 01:40:09 pm
content: The search term you might be looking for is 'site transformer'. These are typically used here in the UK to convert 240V mains to 110V site tools and are usually an isolation transformer with center-tapped earth. Over there in the US there probably isn't much call for conversion, but you might well still have them for isolation of power tools.

author: edavid
author_rank: Super Contributor
timestamp: September 23, 2018, 04:19:47 pm
content: Quote from: dunkemhigh on September 23, 2018, 01:40:09 pmNope, in the US we call them isolation transformers.Back in the hot chassis TV days, it used to be pretty easy to find a service oriented device like the B+K 1653 and 1655, or the various RCA/Viz IsoTaps and IsoVACs. They still turn up occasionally, and can be cheap since people don't know what they are. You also see medical isolation transformers, and they can be really cheap, but it's a matter of luck.

author: JugglingElectrons
author_rank: Contributor
timestamp: September 23, 2018, 05:10:41 pm
content: Quote from: edavid on September 23, 2018, 04:19:47 pmThanks for the B+K and RCA/Viz suggestions. Those models have the exact features I would need. I like how the Viz WP28 has direct and isolated outputs and that it has the wiring diagram if it wasn't clear already. Little touches like that make me enjoy the equipment and appreciate it more. Might have to pick up one of these!