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Dynakit ST-70 How Difficult?

I have used Ungar irons for 40 yrs with no problems. got them when going to school and later. lowcost and reliable.
 
Sir Bakerman said:
When I realized it was beyond my ken I sent it back. Question: will a tube light up if it's faulty?
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Sometimes. If its white on top though, its dead. That and not lighting at all are really the only visual tests you can do. If it glows bright pink, that could indicate gas, but that might also indicate extreme overload caused by some circuit failure.
 
The story continues....
I shipped the ST 35 back to the seller for repair. He sent me pictures yesterday and I am Pi**ed! Some FedEx butterfingers dropped it and broke 4 all of the EL84 tubes. Bent the chassis, and otherwise destroyed my chances of getting this working right away. The weirdest thing is the 2 7247 tubes are missing! They were in there when I shipped it, so either FedEx opened it to assess the damage by dropping it an kept them ,or the guy I sent it to is keeping them to sell and not being honest. They are vintage Dynaco branded Mullards so I guess they are worth a bit of money.
I told the guy to pack it back up ,double box it and I will deal with FedEx. Fortunately I insured it for $500. But I understand FedEx is a PIA when it comes to insurance claims.
Retrospectively, I should have waited and got the kit. Live and learn I guess but I am not a very happy audiophile right now. At least I can give vent here.
FWIW does anyone know of a reputable repair person in the DC/ Baltimore area?
Google only gives me car audio repair shops.

That's all for now.

SB
 
That's a real bummer. But, the good news is the magic is in the transformers, and these are unlikely to have been damaged. While you are waiting for the amp to come back you might read up on ST35 kit builds. e.g. http://diyaudioprojects.com/Schematics/pdf/Dynaco-ST35-Instructions-Manual.pdf

If you tackle the repair as if it were a half built kit you won't go far wrong. You've still got tube pleasure ahead of you.

p.s. Can you post pics of the damage so far? We might be able to give some helpful comments.

Further thought: if the 7247 tubes are toast, you might rebuild the amp using this board, which uses 1 x 12Au7 and 1 x 12AX7. http://www.tubeaudiolab.com/id133.html No affiliation.
 
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You can also get a new SS chassis from dynakitparts.com (but keep the old one for collector value if you sell it later)
 
Great suggestions. I think the chassis can be salvaged. I don't know the full extent of the damage, but I have already considered the re-build idea.

The real issue is the Fed Ex claim I understand they are less than helpful concerning matters like this.

I want to get it back and see and assess the damage. I will post some picture then. The pictures I have are not that great.

SB:tears:
 
Well I just got back from the repair guy. I need new boards and a new multi section capacitor. The power supply and transformers are ok. I can get it fixed for about $150 plus parts.
I sent my claim to Fed Ex so far no word. If Fed Ex does what it is supposed to do I should be fine. If not I have a very expensive doorstop until I can save enough to get the thing fixed. Not a great start to my foray into the tube world.

I am gonna attach a couple of pix to show the damage.The first 3 show the damage the last one shows what I started with. You can't tell from the photo but the boards are broken. Looks like Dynakit parts to the rescue.:tears:

SB
 

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This is almost as building from scratch.
With new boards and tubes, plus a multicap you can use the build manual
to do the job ( unless fedex needs a proffesional repair person )
 
peterh said:
This is almost as building from scratch.
With new boards and tubes, plus a multicap you can use the build manual
to do the job ( unless fedex needs a proffesional repair person )
Click to expand...

No determination from Fed Ex yet. I have yet to decide if I can fix it or to just sell it for parts.

Frustrated to be sure.
 
Don't sell it for parts as the original Output Transformers are best( sonic reasons) to keep so many say!

You can easily fix it yourself as they are super simple PP amps (about the easiest to work on and repair etc.)

Look at Dave's Gillespie's (of AK) EFB mod PCB for the PS as you can greatly increase output tube life and take the sonics to another level! Or do it diy as shown on his site.

http://tronola.com/html/dave_s_lab.html

You will learn lot's as a bonus and save money down the road as you will be able to fix your own gear! Anyway lot's of help here!

Chassis can be easily straightened using wood to protect metal and hammer and vise.

The old PCB's would be brittle to work with anyway as material used weren't so good on most mass produced PCB boards. New ones are fiberglass so much more durable.

Save the old Output Tube sockets as they would be easy to save (bolted on) and are quite high in quality and they can be handy to have anyway. The PCB driver tube ones may be good if they could be de-soldered without breaking them.

You can download the manual on the tubs4hifi and dynakitparts sites.
 
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Well I made an expensive choice and ordered the boards, the multi cap and a power cord ( with an on/off switch). All in plus shipping $200.00 and change.

I received a nice e-mail from Kevin telling me the boards are built as ordered so I have about a weeks wait until I get my parts. Until then I will be searching the house for things to sell to offset the cost. I thought I was getting a nice amp for under $500, so far this has cost over $700, I really hope it works out well. Still kicking myself for not buying the kit to begin with. This was an impulse buy to begin with so lesson learned there.

My past adventures into the restoration / rebuild arena got me a giant killer of a turntable, and an appreciation for things done correctly. I wish I had more soldering skills but I really don't, so paying a little money to have it done correctly makes sense to me.

One thing I learned is to avoid Fed Ex for shipping anything Fragile. Still pi$$ed about that. Live and learn.

SB

P.S. Thanks to all for the encouragement, support etc.:thmbsp:
 
Great idea to keep vintage gear, as I said your probably better off with the vintage Output Trans so don't have any regrets.

Soldering is easy, look on tubelab.com for nice instructions on his PCB boards!

You-tube may be useful also!

I have a beef with them on Broker's Fee's!

I think you have to pack gear in lots of spray foam with wood supports so it can survive a 10-20 foot fall, in my experience!
 
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SB, I think you are taking good decisions with this situation. The advice above sounds just right to me too. The transformers and the chassis are all you need, and you would have needed a new multisection cap (or power board) anyway.

Like the others, I would suggest trying to assemble it yourself, just following the manual. For soldering get a nice temperature controlled iron. (As Frank Sol already said too.) It really makes soldering much easier and better. And use 60/40 tin/lead solder. Save the tech money unless you need help with faultfinding, but honestly there is a lot of help here, and you can take lots of closeup photos of the assembly of your present amp before you rebuild it.
 
Shadow and Dandy,

Thanks. I am considering doing it myself, but it would take me a while to de- solder the components correctly so I can re-use them. Just not that good with a soldering iron.

I have soldered before on my cars when I installed CD players and on my Stratocaster , when I changed the pots. I think I need a better soldering iron.

Right now I just want the parts :D and FedEx to step up and pay me for my troubles.
 
FWIW, I would consider just installing new components on the new boards. You've already got the expensive parts covered one way or another. You can then refer to the original boards as you go, and later sell them on as original ST-35 boards (which they are).
 
Dandy said:
FWIW, I would consider just installing new components on the new boards. You've already got the expensive parts covered one way or another. You can then refer to the original boards as you go, and later sell them on as original ST-35 boards (which they are).
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Dandy,
Unfortunately the original boards are not in good shape. I could probably sell them as is but I would feel shitty knowing I sold something that was not in good shape. I know I am a throwback to ancient times in this regard but I've never had a problem being honest. Other people have had issues regarding my honesty but I see that as their problem not mine.

Sir B
 
hhibrownsbac said:
Id say this was a expensive lesson and that sucks but. The one thing you should take out of this is to NEVER UNDERESTIMATE what shippers are capable of as you have now so painfully seen with your own two eyes. Whether its UPS, FED EX, USPS, or Greyhound. You have to pack this stuff to survive being tossed off a truck, fall off conveyor belt lines, tossed on to porches, and in general you should anticipate that its going to get abused. PACK Accordingly!!!!!! YOU need to make sure that short of them driving over it with their truck it will get there safely.
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After all that they stick a forklift lift arm through the box :tears: true story .
 
Sir Bakerman said:
Dandy,
Unfortunately the original boards are not in good shape. I could probably sell them as is but I would feel shitty knowing I sold something that was not in good shape. I know I am a throwback to ancient times in this regard but I've never had a problem being honest. Other people have had issues regarding my honesty but I see that as their problem not mine.

Sir B
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I know what you mean. Sometimes I feel like a dishonesty absorber.

One thing I've learned though is to immediately file an "item not as described" complaint, when something doesn't work or arrives damaged. The seller is responsible for shipping, period. The buyer should never have to deal with the shipping company, besides perhaps providing photos to support the seller's claim. If a seller asks or demands that you file a shipping claim, refuse, with the explanation that the shipping company will just regard you as a middleman, and that it is his responsibility to make things right.
 
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