Why are these Hammond PTs so similar?

[screefer]

Please help me understand...

Both the 269AX and the 261G6 have 250v. 125-0-125 secondaries with center tap and 6.3v. (no CT) 2 amp filament supplies.

The 269 is 115ma and the 261 is 130ma.

The 269 has 115v, and 125v. primary options and the 261 has only 115v.

The 269 is lighter but 20 bucks more than the 261.

Thanks

 

[lowatter]

Supply and demand and your location/availability perhaps?

 

[Phrygian77]

The 261G6 is 115Vac primary only.

 

[screefer]

The 261G6 is 115Vac primary only.

Is 125vac preferable?

 

[Phrygian77]

@screefer I think I misunderstood your post. The 261G6 is slightly heavier and has a lower source resistance, so less voltage drop under load. It looks like the 261G6 will put out about 301Vac no load.

 

[screefer]

@screefer I think I misunderstood your post. The 261G6 is slightly heavier and has a lower source resistance, so less voltage drop under load. It looks like the 261G6 will put out about 301Vac no load.

Interesting.

I'm still in the learning stage and wish to build a little bedroom amp. The Six Shooter (https://robrobinette.com/SixShooter_Build.htm)
calls for a 125-0-125 secondary so when I saw these two, very similar Pts, I wondered if the cheaper 261 would suffice?

 

[Phrygian77]

I think the 261G6 is probably a bit overkill for that. You don't need that current capacity. B+ max unloaded would be around 212Vdc, so probably a B+ of 200Vdc or a little higher at 125Vac input. That's a little over @robrob's spec, but it would probably be fine as long as the 6CL6 doesn't exceed the 7.5 watts by too much. I'm not sure what the load line looks like, he didn't specify either transformer on that page. At least, I couldn't find it.

 

[Dacious]

The 261G6 is 115Vac primary only.

Is 125vac preferable?

Phrgian means the more expensive is- capable of being wired higher primaries . Hence even though it's lighter and less current capability which might lead you to think it'd be cheaper it's more expensive. The lower cost one will work for you.

 

[screefer]

@Phrygian77
Thanks. I also couldn't find any mention of PT.
I will strive to read and understand the electrical data sheets more closely.

 

[screefer]

The lower cost one will work for you.

Thanks Dacious!

 

[2L man]

Hammond use at lease two different efficiency EI iron cores and better efficiency make transformer bit less heavy.

 

[Phrygian77]

It looks like the 261G6 would yeld a B+ around 191Vdc with a 42mA DC load (8 watts). That's close enough to Rob's 177V.

 

[dan40]

Is 125vac preferable?

With today's wall voltage exceeding 120v, having the 125v option is handy when your filament voltages are running too high on the 115v tap.

 

[screefer]

With today's wall voltage exceeding 120v, having the 125v option is handy when your filament voltages are running too high on the 115v tap.

Good point!
So maybe the 125v option along with the lighter weight would be worth $19 Canadian?

 

[dan40]

So maybe the 125v option along with the lighter weight would be worth $19 Canadian?

If your wall voltages tend to run around 125v, having this extra primary option will help with keeping the filament voltage and secondary voltage in check. If your wall voltage stays around 120v, the cheaper PT should be just fine.

 

[screefer]

If your wall voltages tend to run around 125v, having this extra primary option will help with keeping the filament voltage and secondary voltage in check. If your wall voltage stays around 120v, the cheaper PT should be just fine.

I'm off grid and my 3000 watt Outback inverter puts out around 121v

Thanks for your input!