Fried my Sunpak 383 Super - repair options?

[tomweis]

<p>I fried my Sunpak 383 Super at a fashion show - hammered it too hard I guess. The flash will still power up and fire, but it always fires full blast now; no manual control and no auto thyristor function. <br>

I know it's probably not worth it, but anybody know of a repair shop for these old Sunpaks?<br /><br /> Cheers. Tom</p>

 

[henryp]

<p>A used Vivitar 283 in "9" condition is <$50. A used Vivitar 285HV in "9" condition is about $10 more. Fixing what you have probably is not worth it. YMMV.</p>

<p>Henry Posner<br /><strong>B&H Photo-Video</strong></p>

[peter_simpson1]

<p>Partial schematic here: http://repairfaq.cis.upenn.edu/sam/sp383st1.gif<br /> I think I might start around Q3, the 2SC2785, the switch at the left is the manual power setting switch, and I bet the base of Q2 is hooked to the photoresistor which measures how much light is reflected from the scene in automatic mode.<br /> I think it would be a fun project to fix it, but as Henry points out, for 1/2 hour of your time (valued at $100/hr), you can get a working replacement flash. And "fun" may mean different things to different folks...</p>

<p>Edit: after thinking about it a bit more, I bet T2 or T1 is the problem. T1 seems to open the circuit to the flashtube to kill the flash when the exposure is right. T2 fires, causes T1 to open when the exposure is right. I can see how one of these might fail if it were pushed too hard. </p>

<p>Let us know if you fix it :-)</p>

[rodeo_joe1]

<p>My first suspects would be the thyristors, T1 and T2 as well.<br>

That Vivitar is sold under a variety of names and in various different camera fittings. I have two of them in Nikon dedication + one in Sony/Minolta fit, and I can't say I'm overly impressed. Mine are "Jessop's" branded - from a large retail chain here in the UK that recently went bankrupt. Used price seems to be around 10 to 20 UK pounds, or $15 - $30 US.</p>

<p>I've measured the true guide number of those things at ~22 (metres/100 ISO and 50mm zoom setting), which puts them at the low end of what's currently available. The recycle time from full-power is abysmal and the TTL exposure isn't very consistent. All in all my advice Tom, would be to see this as an opportunity to get something better, rather than waste money and/or time trying to repair that cheap flash.</p>

[bebu_lamar]

<p>If it's underwarranty then they may fix it for free. If not I don't think it's worth to fix it.</p>

[tomweis]

<p>Thanks everyone for posting replies.</p>

<p>Henry,<br>

I have a Vivitar 283 and two 285s. Neither have swivel heads like the Sunpak 383. The 283 is about the same size as the 383, but offers no manual control aside from full power without using a VP-1 module which I have, but it's a pain to switch back and forth between manual and auto thyristor. Also, at ISO 400 the Sunpak 383 allows me to shoot at ƒ4 whereas the 283's maximum auto aperture is ƒ5.6. I prefer the larger aperture.</p>

<p>Yes the 285 offers more manual control out of the box, and allows ƒ4 @ ISO 400 exposures, but the 285 is significantly bigger than the 383, and again doesn't have a swivel head.</p>

<p>The Sunpak 383 Super has what I like: both manual and auto settings built in, tilt and swivel head, and relatively small size. I can live without a zoom head. My only gripes are that it needs more power, and it appears that the 383 is more fragile than I would have guessed.</p>

<p>The Vivitar units do seem more robust. I've used the 285s together on a light stand for group portraits at events, firing them many many times at 1/4 or 1/2 power. On top of that they may be used as room lights during a wedding reception and fire hundreds of times at 1/16th power for three of four hours. Note that I have "vintage" 285s made well before Sakar revived the 285. The Sakar 285s are just terrible - I've seen the poor QC and lousy performance firsthand, and I would never buy one. But I digress.</p>

<p>Peter,<br>

I cannot thank you enough for taking the time to publish the 383 circuit diagram! Whether or not I attempt to repair the flash remains to be seen, but I did take it apart and have accessed the circuit board shown in the drawings. I don't see any obvious burned out diodes (T1, T2 or Q2, Q3), but I am not an expert here and so I suppose diodes may fail without much fanfare. I have a multimeter at work, but am unsure if it has a diode setting.</p>

<p>What I am seeing inside the flash are many little bits of ruby colored plastic, as though some ruby red component has deteriorated or exploded these bits throughout the inside of the flash unit. Any idea what these things are? Is this a clue with regards to the unit's malfunction or is it something different entirely? See the photo I've linked here.<br>

<img src="http://tomweisphoto.com/Z/Sunpak_ruby_dust.jpg" alt="" /> </p>

<p>Rodeo Joe,<br>

Thanks for your input, Rodeo. I have to say it's a Sunpak not a Vivitar as you state.</p>

<p>-----------------------<br>

Lastly, I do own another Sunpak 383 Super in near mint condition. I was lucky enough to get it for $20 and it still had the clear plastic protective decal over the control panel.<br>

Attempting repair on the broken 383 may not strictly be cost effective, but it will certainly be a learning experience which is something I value more than the flash itself (which I obviously like a lot).</p>

<p>Cheers<br>

Tom</p>

[peter_simpson1]

<p>I think the red plastic bits are a "red herring". I know of no component (other than perhaps an LED) that would explode and leave red plastic residue. Perhaps its residue from a lens or lighted button that has disintegrated?<br>

I'm sticking with the high power control circuits - a T1 failure would explain everything and it's in the high power path. T2 would be my next bet. Where you can get replacements for these old dogs is a mystery. <br>

I did Google the part numbers and found some indication that they might have been Mitsubishi part numbers, but I fear they are no longer made. I did find a datasheet for a Mitsubishi CR5AS thyristor, which might be the surface mount version of the T1 part. It's possible that you or an EE friend might be able to use the datasheet specs to find similar parts and test them as replacements. <br>

http://www.digchip.com/datasheets/download_datasheet.php?id=240170&part-number=CR5AS&show=inline</p>

 

[peter_simpson1]

<p>Hi again - I did some research and it looks like this may be a good replacement (current, voltage and gate trigger current all match) for T1. It's $2.10 from Digikey.com. Probably worth a shot:<br>

http://www.digikey.com/product-detail/en/S6010LS2/F5308-ND/967862</p>

<p>If you decide to try it, let us know how it works out!</p>

[tomweis]

<p>Peter,<br>

Again many many thanks for your efforts. If I do attempt the repair - and I intend to - I'll post it here. I don't know when I will give it a shot, but I should do it before I forget how to reassemble the flash. Ha.</p>

[laichungleung]

My experience is that.  If you are using external power only without and AA batteries in the compartment, then no matter what settings you on, the flash will fire full blast.  When you have the batteries in the compartment and attach the external power source then things work as expected, auto or fraction powers.