[Central-Electronics] SS rectifiers? 100V/200V?

[ehertz]

fascinating! I am surprised that the 6AU4 replacement has such a high PIV. I guess as a direct replacement for the tube it needs to match its specs, even thought 4500 PIV seems to be much more than needed in the 100V/200V service.  

Thanks. I copied the CE list in case anyone is interested in some early SS commercial replacements in the transmitters.
Eugene

>-----Original Message-----
>From: John D. Morgan [mailto:kh6u at hawaiiantel.net]
>Sent: Sunday, March 11, 2007 09:56 PM
>To: 'ehertz'
>Subject: Re: [Central-Electronics] SS rectifiers? 100V/200V?
>
>Hi Eugene, I pulled them out and yes they are marked and still legible. 
>They were all made by Sarkes Tarzian - The 5U4 in V23 is replaced by a 
>S-5991. My 1964 Zack catalog says that it is rated for a PIV of 1600 and 
>Max VRms of 1100. It cost $3.50 in '64!. It must have two diodes in series 
>on each leg because the forward voltage drop in 1.4. The 6AU4s in V24 & 25 
>are replaced with two S-5033 which has a PIV of 4500 and Max VRms of 3200. 
>My DVM can't break down the number of diodes in the S-5033. They cost 
>$18.10 each back in '64. I think I was making $2.50 per hour back then so 
>they were fairly expensive. 
> 
>73, 
>Doug KH6U 
> 
>----- Original Message ----- 
>From: "ehertz" <eugene at hertzmail.com> 
>To: "John D. Morgan" <kh6u at hawaiiantel.net> 
>Sent: Sunday, March 11, 2007 1:34 PM 
>Subject: Re: [Central-Electronics] SS rectifiers? 100V/200V? 
> 
> 
>> Thanks, Doug. Any chance there is any manufacturer/part number on the 
>> commercial replacements? thanks again. 
>> 73 Eugene 
>> 
>>>-----Original Message----- 
>>>From: John D. Morgan [mailto:kh6u at hawaiiantel.net] 
>>>Sent: Sunday, March 11, 2007 07:18 PM 
>>>To: 'ehertz' 
>>>Subject: Re: [Central-Electronics] SS rectifiers? 100V/200V? 
>>> 
>>>Hi Eugene, The SS replacements are commercial metal cased short plug in 
>>>units. There are no equalizing resistors, there is no room for them inside 
>>>the units and there are none installed externaly. I measure 148 VDC at the 
>>>output of the 0A2 so the VR tube is doing its job. My line voltage is 118. 
>>>73, 
>>>Doug KH6U 
>>> 
>>>----- Original Message ----- 
>>>From: "ehertz" <eugene at hertzmail.com> 
>>>To: "John D. Morgan" <kh6u at hawaiiantel.net> 
>>>Sent: Sunday, March 11, 2007 2:49 AM 
>>>Subject: Re: [Central-Electronics] SS rectifiers? 100V/200V? 
>>> 
>>> 
>>>thanks a ton! Especially for the voltage measurements. Do you know the 
>>>exact 
>>>nature of the ss rectifiers you have in yours? Are they commerical? Are 
>>>they 
>>>home brew? Any idea the arrangement of components? 1N4007's? equalizing 
>>>resistors? anything? 
>>>thanks again! 
>>> 
>>>>-----Original Message----- 
>>>>From: John D. Morgan [mailto:kh6u at hawaiiantel.net] 
>>>>Sent: Sunday, March 11, 2007 02:25 AM 
>>>>To: 'Eugene Hertz' 
>>>>Subject: Re: [Central-Electronics] SS rectifiers? 100V/200V? 
>>>> 
>>>>Hi Eugene, My 100V had solid state rectifiers installed when I bought it 
>>>>back in '93. My HV measured with a Fluke 77 DVM is 686 VDC at pin 3 of 
>>>>the 
>>>>6550. The highest B+ other than the finals is 391 VDC on pin 7 of V14 the 
>>>>driver. I would go ahead with the solid state replacement, I have had no 
>>>>problems in that area. I did change out all the electrolytics but they 
>>>>never blew - they were just old enough to worry me. There have been some 
>>>>really good articles on the 100/200Vs in Electric Radio. 
>>>>73 & good luck, 
>>>>Doug KH6U 
>>>> 
>>>> 
>>> 
>>> 
>>> 
>> 
>> 
> 
>