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Hi being a new member I had to post something just to break the ice ect... After reading many posts and searching for answers I had stumbled upon this > GLASS AUDIO 6/99. Transformer Polarity Tester. This device works quite well and costs between $10.00-15.00 usd to build !

Hi, welcome!

Little pieces of test equipment like that can prove the handiest on the bench :-)

Cheers!

Has anyone used vintage Heath-kit iron from a SA2 or A111 ? If so what changes are needed for use with the ST35 rev D pcb ? I would like to use the power and also op transformers, but without the tube rectifier I like the idea of SS as it seems better suited for my first build ect... Any help would be greatly appreciated ! Thanks.......

Yes, I and others have built several ST35's with Heathkit iron, works perfectly!

Could you or anyone else please explain what changes if any are needed ? The power transformer is 330-0-330 w/6.3 @ 2.5a x2 also has a 5v for tube rectifier that I dont plan on using. My concern is I may have to change some parts as it may have a higher voltage with todays 117-125vac ect... I'm really not sure how to proceed. Also I have no idea what the specs are on the OP transformers. Both power and OP trans came from a Heathkit #SA2 integrated amp.

Has anyone used Hammond "iron" with good results? Compared to original and reproduction Dynakit parts, how does quality/sound/price compare?

Kyle

antiquekid3 wrote:Has anyone used Hammond "iron" with good results?

I used a pair of Hammond 1620 output transformers on a DIY ST-35. They were much cheaper than either original or reproduction Dynaco transformers. They sounded perfectly fine at normal listening levels, but observations on the oscilloscope suggested they are not capable of producing the same kinds of power levels as the Dynacos. Distortion is evident at relatively low power levels, particularly in the sub 50 Hz region.

I left a few notes about them here:
http://www.diytube.com/phpBB2/viewtopic.php?t=1680

Very interesting! I fully intend to do the same thing with my amp, once it's built. I have a Tek 465, but unfortunately, my 2nd good probe broke the other day...so I'll only be able to measure the input or output at one time now.

I also have a Heathkit WA-3M Williamson amp with a WA-P2 preamp. I'll hopefully test that too, just for fun. I just need to recap the power supply first!

Kyle

The Heathkit transformers will drop right in. Leave the 5v wires unhooked if you use SS rectifiers. Both 6.3v secondarys (grn and brn) will need to be paralleled, make sure they are in phase.

The outputs connect the same as the stock Z-565. Omit C20 and C21. Adjust R30 and R31 to 47k.

Terry, Thank-you for the info ! Im really glad to be able to use the parts I have, being that one only has to omit a couple caps ect.. Also I did not want to alter the ST35 pcb as its much to nice for that ! Now I can start on the chassis, its a Hammond 12 x 10 x 2. Again many thanks Edit: Just wondering ! Did you or any others experience them running at higher voltages, because of variances in line voltage between say 1960 and today ? If so what if any measures were taken to keep things running cool ? I just don't know if using a 50 yr old transformer running hot is a good idea, or simply worrying to much about something I don't completely understand !