Morgan RCA35

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beasleybodyshop
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Morgan RCA35

Post by beasleybodyshop »

So, I was looking at the gut shot for one of these Morgan Amps, and this is what im thinking i see:

tweed deluxe preamp with a long tailed phase inverter

split cathodes on v1 a la plexi marshall

master volume control that you can defeat from the circuit

standard fender TMB tone stack

all being fed into a 6L6 power amp section - without seeing the transformers (it says its a 35 watt amp) maybe using something along the lines of a 40 watt bandmaster or super power transformer? Just trying to wrap my head around this one.
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NickC
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Re: Morgan RCA35

Post by NickC »

I don't know.

But, is anyone else bothered by the lead-dress on the three items marked with a red x in the attached photo?
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Milkmansound
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Re: Morgan RCA35

Post by Milkmansound »

They took great care to mout that cathode ground resistor for the finals on top of the bypass cap maybe forgetting that the whole amp turns upside down - that's a recipe for a dry cap!

The flying lead stuff doesn't bother me so much so long as they wrap them tight around the lugs before soldering
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randalp3000
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Re: Morgan RCA35

Post by randalp3000 »

It might look something like this, but you didn't get it from me :wink:

however that one has a pull bright
tweed baseman/marshall preamp without cathode follower driving tone stack.
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Leo_Gnardo
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Re: Morgan RCA35

Post by Leo_Gnardo »

Milkmansound wrote:They took great care to mout that cathode ground resistor for the finals on top of the bypass cap maybe forgetting that the whole amp turns upside down - that's a recipe for a dry cap!
Roasting el caps with nearby hot resistors was done by plenty of commercial builders too so just following the norm.
The flying lead stuff doesn't bother me so much so long as they wrap them tight around the lugs before soldering
When they wrap the wire on & forget to solder, that bugs me. Seen it happen a lot. Heck even I've done that... put head-slap smiley thing here. :oops:
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ToneMerc
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Re: Morgan RCA35

Post by ToneMerc »

Nearly every gut shot I've of this manf across different models, seemed like there was a race to get it assembled in 30 mins.

TM
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randalp3000
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Re: Morgan RCA35

Post by randalp3000 »

ToneMerc wrote:Nearly every gut shot I've of this manf across different models, seemed like there was a race to get it assembled in 30 mins.

TM
I feel the same way. I've seen 2 with wires not soldered in pots.

found one
[IMG:1024:577]http://i1233.photobucket.com/albums/ff388/randalp3000/amps/IMAG0315_zpsab640787.jpg[/img]
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VacuumVoodoo
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Re: Morgan RCA35

Post by VacuumVoodoo »

NickC wrote: But, is anyone else bothered by the lead-dress on the three items marked with a red x in the attached photo?
This. And over half of solder joints fail already on visual inspection.
Also, where is protective earth cable attached?
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ToneMerc
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Re: Morgan RCA35

Post by ToneMerc »

VacuumVoodoo wrote: This. And over half of solder joints fail already on visual inspection.
Also, where is protective earth cable attached?
I was thinking the same thing, pretty poor craftsmanship for $1700, even if it was only $700.

TM
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randalp3000
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Re: Morgan RCA35

Post by randalp3000 »

OMG I forgot, it's a copy of the 18 Watt Superlite TMB pre with a couple very small tweaks.
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shocki
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Re: Morgan RCA35

Post by shocki »

What kind of power section is this exactly? This really looks like a superlite a lot. Does anybody know what changes should be made to the superlite schematic to run it with 6l6? I would use a Bassman power and output transformer probably.
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Re: Morgan RCA35

Post by shocki »

Ahh just saw the schematic. Great !
eddie25
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Re: Morgan RCA35

Post by eddie25 »

shocki wrote:Ahh just saw the schematic. Great !
That schematic has "350-0-350 unloaded" written on it, but then 370V for the first power supply node, which doesn't add up to me unless I'm missing something?
beasleybodyshop
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Re: Morgan RCA35

Post by beasleybodyshop »

randalp3000 wrote:OMG I forgot, it's a copy of the 18 Watt Superlite TMB pre with a couple very small tweaks.
Randall, was there some sarcasm font tossed in there lol?

since i started this post, ive been inside two of these. I definitely agree with the comment that someone made about these things being assembled together in 30 minutes. The two that i looked into both had wires that were literally one nudge from breaking off.
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Structo
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Re: Morgan RCA35

Post by Structo »

Yeah but, but, but, but, it has Sozo's and Mercury transformers! :D
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