Should I power this thing up?(I HAVE NO VARIAC)

[TechGeek]

Hi all. Yesterday, I got a load of old electronics and all but this Fisher RS-1056 work. The stereo receiver is very dirty and a dirt dobber was found in it, along with some other bugs, and it appears to be from the 70s. Here, let me attach some photos:





I have no variac, so no slow controlled powerup, and I also do not have an ammeter, so no way to measure current draw. It has no blown fuses, and I just want to see this thing work. SOME caps are of Japanese orgins, but there are these unknown quality 'SHOEI' caps. There are no blown and/or bulging caps.

Also, I am wondering how rare this particular unit is. Please help. Thanks.

[ReeceyBurger123]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Be brave it can only go bang right

Probably needs few parts replacing too, maybe use like a 100w light bulb in series with the Ac input to limit current ?

[TechGeek]

Re: Should I power this thing up?(I HAVE NO VARIAC)

more wattage=more current limiting capacity? I could series-string 2 60 watt bulbs for 120 watt load. Where would I hook up the load? In series with the bulbs?

image:

[CapLeaker]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Higher wattage, less resistance. So put in the 60W and good is.

I just would do a visual check over, check the bridge rectifier and the output diodes on the PSU. Other than that, turn it on and see what happens. I had a pre driver fail after the unit ran for 3 minutes. So who knows. Don't be shy. When you turn it on, make sure to measure if you find DC on the speaker outputs. Not sure if this thing has protection (relay click) or not.

[ReeceyBurger123]

Re: Should I power this thing up?(I HAVE NO VARIAC)

I said 100 as there would hopefully be more of a drop on the input hopefully help as much as possible just to get the caps energised a little. Also yeah 60 should be fine though if you only have em on hand see what it does, never know it might work

However the caps will need to be changed in good time as they are old.

[TechGeek]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Could I just plug it straight into the wall(no ballasting/full line voltage)?

[TechGeek]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Higher wattage, less resistance. So put in the 60W and good is.

I just would do a visual check over, check the bridge rectifier and the output diodes on the PSU. Other than that, turn it on and see what happens. I had a pre driver fail after the unit ran for 3 minutes. So who knows. Don't be shy. When you turn it on, make sure to measure if you find DC on the speaker outputs. Not sure if this thing has protection (relay click) or not.

Why do I need to check for DC on the speaker outputs? And how much DC?

[dmill89]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Could I just plug it straight into the wall(no ballasting/full line voltage)?

If you feel lucky. I've done it plenty of times with 40-50+ year old receivers/radios (just plugged them in an hit the switch), but there is always the possibility it could go bang and/or release the magic blue smoke.

Looks like RS-1056s are going for between $50-175 on eBay depending on condition, so it has some value, but isn't exceptionally valuable (probably about average for a quality 90WPC receiver from that time period), so there isn't a ton of risk in doing this. (If you want your head to explode look at what Marantz 2270/2275s are selling for, a good one with a wood case can sell for $1k+ and even non working they can go for $300+)

[TechGeek]

Re: Should I power this thing up?(I HAVE NO VARIAC)

I did a quick Google search and found nothing but mainly eBay ads. Looking on eBay for it turns up about nothing, so maybe either everyone's keeping theirs or these sets are becoming all but common.

[goontron]

Re: Should I power this thing up?(I HAVE NO VARIAC)

If you feel lucky. I've done it plenty of times with 40-50+ year old receivers/radios (just plugged them in an hit the switch), but there is always the possibility it could go bang and/or release the magic blue smoke.

Looks like RS-1056s are going for between $50-175 on eBay depending on condition, so it has some value, but isn't exceptionally valuable (probably about average for a quality 90WPC receiver from that time period), so there isn't a ton of risk in doing this. (If you want your head to explode look at what Marantz 2270/2275s are selling for, a good one with a wood case can sell for $1k+ and even non working they can go for $300+)

The Marantz 2325 is going for $1,175.00, i don't get why. These fuckers are deaf! They can't pick up a 1 watt FM transmitter next to the bloody antenna! Yet a yamaha CR640 has no problem picking it up from across the room! Marantz garbage!

[TechGeek]

Re: Should I power this thing up?(I HAVE NO VARIAC)

So, I have a good set that's starting to get moderately unavailable?

[dmill89]

Re: Should I power this thing up?(I HAVE NO VARIAC)

The Marantz 2325 is going for $1,175.00, i don't get why. These fuckers are deaf! They can't pick up a 1 watt FM transmitter next to the bloody antenna! Yet a yamaha CR640 has no problem picking it up from across the room! Marantz garbage!

While I generally don't have any complaints with Marantz (but also realize other makes have receivers that are as good or better), the prices have gotten absolutely ridiculous. I have a model 2015 receiver I bought about 10 years ago for around $35 in excellent condition (only needed one bulb replaced), today those are going for around $100-250 for a little 15 WPC receiver with 4 inputs (2 tape, phono, Aux). When I bought the 2015, 2270/2275s were going for $200-300 fully working and in excellent cosmetic condition and $400-500 fully refurbished with new caps and lamps and calibrated, which I thought was pretty reasonable (not "cheap", but ok for a receiver with those capabilities and build quality), today you are looking at double that or more (and a lot more if you want a wood case), there are just too many good alternatives out there for far more reasonable prices to justify that.

[dmill89]

Re: Should I power this thing up?(I HAVE NO VARIAC)

I did a quick Google search and found nothing but mainly eBay ads. Looking on eBay for it turns up about nothing, so maybe either everyone's keeping theirs or these sets are becoming all but common.

I didn't find any active listings for that particular model (though I did see some similar ones), but a search of completed listings (these go back 90 days) found 3 one for $51, one for $135 and one for $175, the two more expensive ones were tested and cleaned (though it doesn't appear any internal work was done on these, one that has been recapped/re-lamped may be worth more, but maybe not hard to say) and from established sellers (while the $51 one was from a 0 feed back seller with a limited description).

[rhomanski]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Sorry to tell you this. Fisher was sold by the original owner. Anything that says "Studio Standard" was made after the sale and is not considered to be valuable at all. I have a system I bought in 1984. It just isn't as good as one of the big three, Pioneer, Sansui, or Marantz. It's worth saving. It just won't ever be as valuable as one of the other three. People are discovering what real music can sound like and ditching their digital equipment. That's why you see prices rising on all the old stuff. In the 80's and 90's you couldn't give it away. Now, it's in high demand.

[dmill89]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Sorry to tell you this. Fisher was sold by the original owner. Anything that says "Studio Standard" was made after the sale and is not considered to be valuable at all. I have a system I bought in 1984. It just isn't as good as one of the big three, Pioneer, Sansui, or Marantz. It's worth saving. It just won't ever be as valuable as one of the other three. People are discovering what real music can sound like and ditching their digital equipment. That's why you see prices rising on all the old stuff. In the 80's and 90's you couldn't give it away. Now, it's in high demand.

It looks like when the RS-1056 was made ~1977, Fisher was owned by Sanyo, like you said it isn't "bad" but isn't anything particularly "special" either.

[budm]

Re: Should I power this thing up?(I HAVE NO VARIAC)

This Fisher is made by Sanyo when they bought out Fisher name, so basically a Sanyo with Fisher name on it.
You can use 60 Watt lamp for now, or use two 60W in PARALLEL to give 120 W.

[kaboom]

Re: Should I power this thing up?(I HAVE NO VARIAC)

I have no variac, so no slow controlled powerup

That's a big myth. A Variac doesn't limit current. How would it? It's nothing but a variable autoformer- a dead short on its output will pull excess current even with the knob way down.


IOW, even with a Variac, you still use a "dim bulb." Try a 40W lamp in series with the line, and verify all power supply voltages begin to come up. Then a 60W, 75. The amp should be working at this point- check across emitter resistors for excessive voltage= means amp bias "ran away." Fix this before larger lamp or full line voltage.

DC offset should be below 250mV at the point amp comes up on reduced voltage. Some had more offset at reduced voltage- long tailed pair isn't quite symmetrical at this point. If offset minimal, a larger lamp/higher voltage should make DC offset decrease.

If there are offset and bias pots, clean them! A bad bias pot can take the output/driver transistors out, as well as other components. A set of four Motorola/Onsemi 2119x is about $20.

It looks like when the RS-1056 was made ~1977, Fisher was owned by Sanyo, like you said it isn't "bad" but isn't anything particularly "special" either.

True, but there were certainly worse. I won't even mention "Soundesign."

[jiroy]

Re: Should I power this thing up?(I HAVE NO VARIAC)

Since no silicons are shorted , fuses are okay , then why not ..Capacitors , if dried , will show different symptoms , but not much more than the fuse can handle .
Those Fisher were something , Akai are better , and the twos were formidable if equipped with JBL's , the good old days .

[TechGeek]

Re: Should I power this thing up?(I HAVE NO VARIAC)

How do I check transistors for shorts and/or rectifiers? The output diodes on the PSU are far from shorted, one reads almost 200K resistance.

[jiroy]

Re: Should I power this thing up?(I HAVE NO VARIAC)

How do I check transistors for shorts and/or rectifiers? The output diodes on the PSU are far from shorted, one reads almost 200K resistance.

A regular diode would pass the voltage one way and block it the other way , put your DMM on Diode level , and test diodes in the PS . Rectifiers are primarily diodes , like one rectifier is composed from 4 diodes typically , so you measure rectifiers like a 4 diodes measuring ..
Note that some diodes could give erroneous measures on board if it's relayed with some resistance . In such case , you have to remove one leg of the diode .