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 The little general that maybe never was
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 Return to top of page · Post #: 76 · Written at 10:33:27 PM on 11 August 2020.
Tallar Carl's avatar
 Location: Latham, ACT
 Member since 21 February 2015
 Member #: 1705
 Postcount: 2149

Haaa Jimb our dining room quickly became my radio room lol. Great minds think alike.


 
 Return to top of page · Post #: 77 · Written at 11:20:36 PM on 11 August 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

I am not terribly phased by being cooped up in the house as it does not happen. It has taken as noted (with interruptions) since March to finally clear out all of the tree rubbish in the shelter belts. Several hundred trees and two major storms do make a mess & accidents & health issues do not help.

The Garages here are a tad full, the work horse tractor, was actually overhauled in the caravan skillion, on the shearing shed, as there is no room in the skillion on Shed 1. Its got 1 Tractor non commercially repairable (not mine), one 1958 MKII Zephyr Ute (Original Reg plates) Farm tow motor. The Road car 2001 Mazda (needs getting rid of) and the baby sit, 2008 A4 Audi Quatro (Tractor, runs on diesel). Motor Bike currently parks on the house Verandah.

Lots of Wildlife in 140 acres without leaving home. Even the new Wood Duck, Ducklings are there to remind me of the Nationals. At the slightest hint of a problem, they go to water.

EBF2 in English: http://frank.yueksel.org/sheets/046/e/EBF2.pdf. HMV used it in 661 to sub for 6B8 I have mentioned that. There were circuit changes & it was probably the same reason it was in Little General. WD scarpered off with all of the 6B8's.

Marc


 
 Return to top of page · Post #: 78 · Written at 10:01:10 AM on 12 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

I hope to get back into it today.I am a bit put off by this wave change switch assembly .It is very bulky and difficult to install on top of the other components and I guess I have stalled. I Am not even sure it is salvalagble I don't need the shortwave band I was only going to use it to keep it true to the published article.
Marc your place is a far cry from our 534 sq meters . I do not have the room for an additional shed . The shed I have is the a 5x10 metal shed which is all we were allowed here and it is stuffed full as you can well imagine .
So let's see what progress I can make today if any.
Regards Jim.


 
 Return to top of page · Post #: 79 · Written at 9:09:03 AM on 13 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Well yesterday produced no results to the naked eye. I decided the wave change unit looked to far gone and I don't have a circuit of it's internals and no labelling I did manage to work out most connections but was not sure of the osc.coil and I lost my way through the switch contacts it also took up a huge amount of room on this very compact chassis 220 mm X 145 mm so I am fitting a BC band osc.and aerial coil assembly . I had to make up a mounting bracket for this . I did a trial fitt of the radio back into the case and it did not fit due to the voice coil speaker. I had to reduce the height of the speaker mounting block , did another trial fit the speaker now cleared but the output transformer fouled on the top of the case . The case had a 4mm piece of timber inside the top of the case so I removed a section of this and now it just slides in. The. Compactness of this has caused me a few problems. So I wonder if today will see any positive progress
Regards Jim.


 
 Return to top of page · Post #: 80 · Written at 9:35:05 AM on 13 August 2020.
Fred Lever's Gravatar
 Location: Toongabbie, NSW
 Member since 19 November 2015
 Member #: 1828
 Postcount: 1245

JimB.
Good progress!
Forward!
And upwards too.
Fred.


 
 Return to top of page · Post #: 81 · Written at 10:27:23 AM on 13 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thanks Fred I am going to ask Brad if he can upload a photo of the dinning room table construction site.
RegardsJim

Tea Table


 
 Return to top of page · Post #: 82 · Written at 10:19:18 PM on 13 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Well it is altogether unfortunately not operational . I am not suprised by that as I was wiring it up I spotted several silly mistakes I had made and had to back track there must be more yet to be found. I suspect they will be around the front end aerial and oscillator sections.
The audio end has something there because it is motor boating and squealing . So all is not entirely lost at this point.
I will start with voltage checks on the 6J8 and EBF2 .
The condition of the EBF2 is unknown and not sure if I have a replacement, I might have it is not a common valve and the filiaments are wired to pins 1 and 8 which narrows down a direct replacement.
Regards Jim


 
 Return to top of page · Post #: 83 · Written at 11:13:32 PM on 13 August 2020.
Marcc's avatar
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5239

With appropriate mods one can go to 6B8 refer to HMV 661.

Whilst the computers are on a custom built (onsite) table with six legs & levellers (uneven floor) The radio bench is actually a kitchen table. The advantage is that the shelving above it has the Oscilloscopes, Generators & frequency counter. Which limits the number of feral wires, leaving room for a vastly different array of clutter. Like Chainsaws.

Marc


 
 Return to top of page · Post #: 84 · Written at 2:50:32 PM on 14 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Hi again all.
I am a bit stumped with this. It is a front end fault and for me they are the hardest kind. The voltages on the valves all appear to be correct the IF end and output are OK feeding the generator in on the grid of the EBF2 the IF coils can be peaked . If I have the generator somewhere near the antenna lead the IF is getting through. I suspect the oscillator coil. Not sure of what they should measure it seems very low, the primary side 2.2 ohms and the secondary about 0.8 ohm. One thing which maybe a clue when the tuning gang is fully meshed the IF through the antenna side is strong and clear , rotating the gang away from the low end breaks into motor boating and Howells and whistles
Any thoughts ?


 
 Return to top of page · Post #: 85 · Written at 3:54:27 PM on 14 August 2020.
Brad's avatar
 Administrator
 Location: Naremburn, NSW
 Member since 15 November 2005
 Member #: 1
 Postcount: 7290

Photo uploaded to Post 81.


‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾
A valve a day keeps the transistor away...

 
 Return to top of page · Post #: 86 · Written at 4:38:05 PM on 14 August 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2363

Sounds like the oscillator isn't running. Measure G1 of the converter via a 100k resistor. What do you get?


 
 Return to top of page · Post #: 87 · Written at 5:34:50 PM on 14 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Thank you Brad for the upload.
Regards Jim


 
 Return to top of page · Post #: 88 · Written at 5:55:58 PM on 14 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Hi ! Ian The top cap g1 of the EBF 2 measures 300 mv via a 100K resistor measurement taken from ground on a digital meter.
Regards Jim


 
 Return to top of page · Post #: 89 · Written at 6:36:11 PM on 14 August 2020.
Ian Robertson's Gravatar
 Location: Belrose, NSW
 Member since 31 December 2015
 Member #: 1844
 Postcount: 2363

No, the converter valve (6A8? No, 6J8), not the IF. And G1 is not the top cap. It's Pin 5.


 
 Return to top of page · Post #: 90 · Written at 7:10:50 PM on 14 August 2020.
Jimb's Gravatar
 Location: Kanahooka, NSW
 Member since 18 November 2016
 Member #: 2012
 Postcount: 712

Hi Ian .
Sorry misinterpretation ok 6J6 pin 5 digital meter to ground via 100k resistor + 2.1 Volts . Analogue meter to ground via 100k resistor + 1.2 volts.. Moving the gang until motor boating occurs drops the + 2.1 volts to 1.6 volts.on digital meter.
Regards Jim


 
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