5U4G U52 CV575 CV1071 CV1575 GZ31 VU71 VALVE RECTIFIER VARIOUS MANUFACTURERS

Here we have a single U52 DIRECTLY HEATED TAPE FILAMENT rectifier manufactured by Osram at their Hammersmith UK factory.

This device carries the white artouche CV575 markings in white printdisplaying the date code HD which equates to April 1953

Highly sought after not just for the impressive current delivery performance but for it's extreme musicality and deep bass extension in hifi applications this is a nice lot indeed. Even more so as it's in the delicious bulbous envelope presentatiion which not only enhances sound quality but looks wonderful. . No wonder all the high end magazines rave about these beauties.

This valve shows excellent bright getter and has the inverted cup getter pan situated down by the glass pinch, the valve base is tight to the envelope but there is some loose valve cement caught within the base , however, more importantly it tests as EXCELLENT using my Avo VCM163 valve tester. This exquisite device has good sharp getter, the classic U52 envelope shape and the trademark rounded brown low loss micanol base  - simply super.

Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty

This RCA tall form ST envelope 5U4G valve shows excellent bright getter and tests as EXCELLENT using my Avo VCM163 valve tester. The brown micanol base is tight to the envelope. Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty.

Here we have a single U52 DIRECTLY HEATED TAPE FILAMENT rectifier manufactured by Osram at their Hammersmith UK factory during March 1954.

This device carries the white artouche CV575 markings in white printdisplaying the date code JC which equates tom March 1954

Highly sought after not just for the impressive current delivery performance but for it's extreme musicality and deep bass extension in hifi applications this is a nice lot indeed. Even more so as it's in the delicious bulbous envelope presentatiion which not only enhances sound quality but looks wonderful. . No wonder all the high end magazines rave about these beauties.

This valve shows excellent bright getter and has the inverted cup getter pan situated down by the glass pinch, the valve base is tight to the envelope but there is some loose valve cement caught within the base , however, more importantly it tests as EXCELLENT using my Avo VCM163 valve tester. This exquisite device has good sharp getter, the classic U52 envelope shape and the trademark rounded brown low loss micanol base - simply super.

Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty

These are a rather special find!  Today, on offer we have a pair of 5U4G, manufactured specially for the UK military valve and hence marked CV575, indeed, these are Air Ministry devices as it has it's shrink sleeve applied to the glass-base junction, a palliative measure that only the Air Ministry used - many customers panic when they see this sleeving but believe me, this was applied in RAF stores during the early 1950s.

It is a shame that one of the device has faint inking, however, what is especially interesting though is that it the device with perfect markings shows a factory code J  for Mullard Tottenham - the old British Tungsram works.   What is even more interesting is that both of these show a date code of November 1956 which is the very year that Mullard closed Tottenham so this must be one of the very last devices made there.

This ex military RCA tall form ST envelope 5U4G valve shows excellent bright getter and tests as EXCELLENT using my Avo VCM163 valve tester. Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty.

This is a rather special device, It's a 5U4G, manufactured by Mullard in the UK - it's an old shield device with mint white print and the giveaway of seeing an American RITMA type valve by Mullard that is British made is that it must have come from Mullard Tottenham - the old British Tungsram works. This makes it a very scarce device as this factory was only in production for Mullard for a period of four years from 1952 to 1956.

The envelope is tight to the BLACK low lossbase and the device tests as EXCELLENT using my Avo VCM163 valve tester. Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable and scarce beauty

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty 

Here we have a single U52 DIRECTLY HEATED TAPE FILAMENT rectifier manufactured by Marconi UK sometime during the 1950's. 

This device carries tvery good white print as can be seen from the photograph.

Highly sought after not just for the impressive current delivery performance but for it's extreme musicality and deep bass extension in hifi applications this is a nice lot indeed. Even more so as it's in the delicious bulbous envelope presentatiion which not only enhances sound quality but looks wonderful. . No wonder all the high end magazines rave about these beauties.

This valve shows excellent bright getter and has the inverted cup getter pan situated down by the glass pinch. However, more importantly it tests as EXCELLENT using my Avo VCM163 valve tester. This exquisite device has good sharp getter, the classic U52 envelope shape and the trademark rounded BLACK low loss micanol base which is tight to the envelope - simply super.

Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty

This beautiful Joint-Army-NAvy ex military device is ex equipment but gives a full emission test on our AVO VCM163.  It has the scarce 5 ridged charcoal anode electrode cage  and is a very very nice valve indeed - scarcely offeredd, keenly sought, well, here's one on offer today!

Highly sought after not just for the impressive current delivery performance but for it's extreme musicality and deep bass extension in hifi applications this is a nice lot indeed. Even more so as it's in the delicious bulbous envelope presentatiion which not only enhances sound quality but looks wonderful. . No wonder all the high end magazines rave about these beauties.

This valve shows the perfect early etched print 5U4G notation within the classic GEC-Osram cartouche  With excellent bright getter and the inverted cup getter pan situated down by the glass pinch, the valve base is tight to the envelopewith a slight amount of loose cement caught inside the base , more importantly it tests as EXCELLENT using my Avo VCM163 valve tester. This exquisite device has good sharp getter, the classic U52 envelope shape and the trademark rounded black low loss micanol base - simply super.

Device test data: Ia = 120.0mA for both diode sections.

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this venerable beauty  

This beautiful Joint-Army-NAvy ex military device is ex equipment but gives a full emission test on our AVO VCM163. It has the scarce 5 ridged charcoal anode electrode cage and is a very very nice valve indeed - scarcely offeredd, keenly sought, well, here's one on offer today! 

This beautiful Air Ministry WW2 ex military device is ex equipment but gives a full emission test on our AVO VCM163. It has the smooth light charcoal anode electrode cage and is a very very nice valve indeed.  The envelope carries an etched 5U4G 110E/47 cartoughe and the base carries red inked printing in addition - a scarcely offered WW2 variant of this device, keenly sought, well, here's one on offer today! 

Here we have an Osram U52 DIRECTLY HEATED TAPE FILAMENT rectifier  manufactured by Osram at their Hammersmith UK factory.

This device carries a white inked cartouche which list the factory code, KB/Z, the type notation CV575 - which denotes a military high grade device and the date code HC which corresponds to March 1953, the classic U52 envelope is tight to the trademark rounded black low loss micanol base and a small amount of loose valve cement is trapped inside.

Highly sought after not just for the impressive current delivery performance but for it's extreme musicality and deep bass extension in hifi applications this is a nice lot indeed. Even more so as it's in the delicious bulbous envelope presentatiion which not only enhances sound quality but looks wonderful. . No wonder all the high end magazines rave about these beauties.

The valve shows excellent bright getter and has the inverted cup getter pan situated down by the glass pinch. However, more importantly, both test as EXCELLENT using my Avo VCM163 valve tester. V1 & V2 Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this beautiful device.

Here we have an Osram U52 DIRECTLY HEATED TAPE FILAMENT rectifier manufactured by Osram at their Hammersmith UK factory.

This device carries a white inked cartouche which list the factory code, KB/Z, the type notation CV575 - which denotes a military high grade device and the date code HC which corresponds to March 1953, the classic U52 envelope is tight to the trademark rounded black low loss micanol base and a small amount of loose valve cement is trapped inside.

Highly sought after not just for the impressive current delivery performance but for it's extreme musicality and deep bass extension in hifi applications this is a nice lot indeed. Even more so as it's in the delicious bulbous envelope presentatiion which not only enhances sound quality but looks wonderful. . No wonder all the high end magazines rave about these beauties.

The valve shows excellent bright getter and has the inverted cup getter pan situated down by the glass pinch. However, more importantly, both test as EXCELLENT using my Avo VCM163 valve tester.

Device test data: Ia = 120.0mA for both diode sections

Device specification 120mA delivery for both diode sections. So you can see we have 100% emission from this beautiful device.