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Hammond for Ultra?

PostPosted: Tue Jan 06, 2015 7:55 am
by opa1
I'm looking at building the Ultra and have a few questions about the PT. I have a NIB, Hammond 272HX and Transcender TT-312-OT OPT's that were for another project. I'd like to use these if possible. The specs on the PT are 600v CT. @ 230ma./5v CT @ 3a / 6.3 CT @ 6a. Will I be able to use the Hammond? Would some of the PS resistor/cap values need to be changed to correct voltage?

Mark

Re: Hammond for Ultra?

PostPosted: Tue Jan 06, 2015 9:06 am
by battradio
http://www.transcendar.com/2.html , http://www.angela.com/hammondclassicenc ... rmers.aspx ,https://www.edcorusa.com/xpwr005

With what you have in the way of a power transformer and output transfomers you could use 6L6GC's , EL34's or 6550's pretty much interchangeable with the correct cathode resistor and with the lower B+ voltage R21 might need to be eliminated .

Re: Hammond for Ultra?

PostPosted: Tue Jan 06, 2015 1:08 pm
by Shannon Parks
opa1 wrote:I'm looking at building the Ultra and have a few questions about the PT. I have a NIB, Hammond 272HX and Transcender TT-312-OT OPT's that were for another project. I'd like to use these if possible. The specs on the PT are 600v CT. @ 230ma./5v CT @ 3a / 6.3 CT @ 6a. Will I be able to use the Hammond? Would some of the PS resistor/cap values need to be changed to correct voltage?

Mark


Those would all work perfectly, Mark.

Shannon

Re: Hammond for Ultra?

PostPosted: Tue Jan 06, 2015 3:31 pm
by opa1
Great! I was worried about the 6.3 amp rating at 6amps being too much for the filaments. So the PS valves in the BOM will work as they are? I haven't tried the setup in PSUDII yet. I'll try it with and without the R21 100Ω 3W if it will let me.

I have a bunch of Kiwame resistors too but they might be to big for the PCB (2W). The valves of R3-R4, R13-R14 grid stoppers are 1kΩ. Can these be upped to 1.5K? Also for the R1-R2 I have some 470K Kiwames. If these wont work I'll just order from mouser.

I checked the link to the mouser BOM. The .22 coupling caps and the R23 330k are not available. I have some .22 k42y Russian caps. I couldn't find the 330kΩ resistor on the schematic? While searching the threads I saw that you were updating the BOM. Should I wait to order from mouser?
Lots of questions. =:o
Mark

Re: Hammond for Ultra?

PostPosted: Tue Jan 06, 2015 3:35 pm
by opa1
I found R23 in the 6L6 PS schematic. It's 300kΩ.

Re: Hammond for Ultra?

PostPosted: Tue Jan 06, 2015 5:47 pm
by Shannon Parks
R23 is the bleeder for the power supply. Any 2W, non-metal film (we need high voltage rating) will do. Re-doing the Budgie SE manual - not the Clementine. But obviously it sounds like I need to go over all the BOMs and sub as needed. Otherwise, the standard BOM should work fine for your transformers.

Shannon

Re: Hammond for Ultra?

PostPosted: Thu Jan 08, 2015 2:07 pm
by opa1
Thanks! I sold the 272HX. So now I'll get the correct PT.

Re: Hammond for Ultra?

PostPosted: Thu Jan 08, 2015 2:35 pm
by battradio
http://www.ebay.com/itm/PT330M-USA-POWE ... 23461c3e94

These are available with out the edcor wait ,

it costs about $15 more though but does have the taps for bias and a optional 5 volt rectifier tube .

Re: Hammond for Ultra?

PostPosted: Fri Jan 09, 2015 5:15 pm
by opa1
Mark, Have you tried any of there products? It looks like it should work. Is the 140ma enough. The XPWR is 180ma. I just ordered the PCB. Mouser is next. The 10k resistor is backorderd, looks like any 10k 1w metal oxide should work.

Re: Hammond for Ultra?

PostPosted: Fri Jan 09, 2015 11:36 pm
by battradio
opa1 wrote:Mark, Have you tried any of there products? It looks like it should work. Is the 140ma enough. The XPWR is 180ma. I just ordered the PCB. Mouser is next. The 10k resistor is backorderd, looks like any 10k 1w metal oxide should work.


The 140 Ma would limit the bias to each output to 70 Ma , haven't tried that one

Re: Hammond for Ultra?

PostPosted: Sat Jan 10, 2015 11:20 am
by opa1
Shannon Parks wrote:R23 is the bleeder for the power supply. Any 2W, non-metal film (we need high voltage rating) will do. Re-doing the Budgie SE manual - not the Clementine. But obviously it sounds like I need to go over all the BOMs and sub as needed. Otherwise, the standard BOM should work fine for your transformers.

Shannon

I checked mouser for a 330K 2W metal oxide. All are back ordered. What other ohm resistor will work for R23?
I did find a 282-300K-RC. They have a 261-10K-RC for R22 to replace the 281-10K-RC. It is slightly larger in size.
I'm also thinking about using the PA774. Is this a bad idea? Considering it because there's no wait time.

Re: Hammond for Ultra?

PostPosted: Mon Jan 12, 2015 1:36 pm
by opa1
PCB arrived today!! (banana) Looks great.

Re: Hammond for Ultra?

PostPosted: Mon Jan 12, 2015 2:36 pm
by battradio
opa1 wrote:PCB arrived today!! (banana) Looks great.


What are you going to use for a chassis

Re: Hammond for Ultra?

PostPosted: Mon Jan 12, 2015 4:54 pm
by opa1
I'm going to use a aluminum plate with wood frame. I have a few sheets of aluminum I bought from online metals. Did you look at the resistor change in the former post? I need to order and want to make sure they will sub for the parts.

Mark

Re: Hammond for Ultra?

PostPosted: Mon Jan 12, 2015 5:34 pm
by battradio
For the 330K 3 watt resistor going up t0 360K or 390 k won't hurt any thing , the other resistor is ok , and the PA774 is fine also

http://triodeelectronics.com/pa7dynst35sc.html

http://www.mouser.com/Passive-Component ... 0k&FS=True