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ozjohn

Sterling Member
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Everything posted by ozjohn

  1. Just finished watching Robson Green's Hadrian's wall walk. Apparently there are 56 phallic symbols on the wall. This time it was described as a good luck charm and used to ward off the evil eye.
  2. ozjohn

    Ebay's Worst Offerings

    IMO still looks like wear to me especially the obverse. The highest points are all worn with the only detail on the lower parts of the hair where contact wear is minimized. In my experience lightly struck coins of this era are for the most part are patchy. For example a George V first type florin. On the obverse the King's ear, and the hair just above are the most likely affected with the lions on the shield on the reverse corresponding to the same area similarly affected with the rest of the coin remaining fairly sharp As for technical grade I think PCGS etc. should in their opinion note that the coin is a lightly struck example. I have and old set of encyclopedias called The Children's Encyclopedia by Arthur Mee that shows the operation of the Royal Mint in the 1930s. One thing that struck me, pardon the pun was the visual inspection the freshly minted coins shown as part of the process. You would hope that most of the really badly minted coins would have been culled at this stage of production.
  3. ozjohn

    Ebay's Worst Offerings

    https://www.ebay.co.uk/itm/224490919818?hash=item3444b3978a:g:QOoAAOSwYjReLcLD Saw this one on ebay.uk a PCGS slabbed coin graded AU-55. Also included a screen shot of the PCGS photo. I think this coin is badly over graded and think F-15 would be a more accurate grading as there is considerable wear on the obverse that cannot be putdown to a light strike. The reverse although appears to be less worn is not anywhere near to AU grades. Again I do not thing these professional graders are producing a constant product. I know you should buy the coin not the assigned grade but new collectors can be badly miss lead by this sort of miss grading. A PCGS AU-55 grading example is included for comparison.
  4. Had the first AZ shot in May. No side effects at all. Second shot due in July. Vaccination hesitancy rife in Australia but the recent Victoria cases have focused people’s minds and vaccination rates have accelerated.
  5. Saw this one in Pompeii on a trip to Italy. According to the guide it was pointing the way to a brothel.
  6. The other thing .There doesn’t seem.to be any shortage of 1927 proof florins.I now have two. The one posted was brought as it was a slabbed example at a good price and I am also trying to assemble a 1927 proof set apart from my date collection . I take your point about the halfcrown but I think there is some thought, perhaps wrong, that the new design of the halfcrown was issued as currently issues along with 6 million odd old design coins. Perhaps this accounts for the higher price commanded by the proof 1927 florins
  7. Not very well put in the first post. " I wonder why it's more expensive as only 15000 were issued .......?." Better I wonder why they aren't more expensive as only 15000 were issued ......... ?
  8. My latest coin received today a 1927 proof florin. I wonder why it's more expensive as only 15000 were issued only in proof with no circulation florins for 1927. This one was a good price at $US 125.00
  9. ozjohn

    CGS Grading

    https://www.ebay.co.uk/itm/254956110884?hash=item3b5c918424:g:A5YAAOSw609c5XNK This coin has been graded at CGS 80. I have a coin of the same date and TPG that has a CGS 60 grading assigned. Personally I think the coin I have is of a higher grade than the one listed on Ebay. As I have observed before the whole point of TPGers is consistency in grading and confidence in the product you are buying. This one fails on both counts
  10. ozjohn

    CGS Grading

    Some of the best images of coins I have were from scans on a flat bed scanner. This is probably due to the coin being very close to the light source eliminating reflections from the plastic surface.
  11. ozjohn

    CGS Grading

    Just as a belated aside my coin was photographed thru plastic but presents IMO as a better coin than the subject of this discussion.
  12. ozjohn

    CGS Grading

    The mark on the cheek as does the flatness of the veil look like wear to me. I agree it can be difficult to photo graph thru the plastic. Perhaps CGS would help their grading reputation by allowing access to their pictures of coins as do PCGS .
  13. ozjohn

    CGS Grading

    I note the price for this item is low perhaps because of the quality of the coin. For example the following coin https://www.sterlingcurrency.com.au/1899-silver-florin-victoria-s-3939-pcgs-ms64 has a price tag of $AU 425 about GBP 236 also cataloged at GBP 225, Spink Coins of England 2016.
  14. I use Firefox on my PC and notebook with a DuckDuckGo plugin and also the Express VPN and have on issues posting to these forums.
  15. That is the permeability constant ur of magnetic materials change with the current exciting it where as the permittivity of a dielectric remains constant.
  16. That's right I suspect the magnetic materials used in modern speakers is much improved over that used in the 1960s also large speakers were always better for good bass response. I've always liked the idea of electrostatic speakers from the point of view they are linear because the dielectric stays the same with different voltages applied where as magnetic materials change as the current exciting it is changed. Quad brought out some in the late 1950s and still make them to this day along with Vacuum tube amps. They are probably expensive and may be limited in their power handling.
  17. I had a look into the difference between the KT 66 and KT 88 tubes. The KT 88 was an older tube and of a higher power rating than the KT 66. KT 66s were probably used in domestic HiFi amps as 20 watts output power was deemed sufficient as the dynamic range of vinyl LPs was about 45 dB and with an average listening level of about 0.5 w to 1 w the headroom was sufficient to prevent excessive distortion. There were also a lot of power amps based on the Wireless World Williamson amplifier that delivered 10 w output power using EL 84 tubes in push pull. Most modern domestic HiFi amps are in excess of 50 w output power to accomodate the much increased potential dynamic range of 100 dB offered by CD and other digital streaming as the dynamic range is determined by the number of quantisation levels during digitisation rather than a voltage level or the distance a stylus can travel on a vinyl record.
  18. Very nice coin but I feel sorry for the horse, he has a very sad face.
  19. My Grandfather had a pewter tankard with a glass bottom. On the glass bottom there was a picture of a man on the gallows and an inscription, "Good to the Last Drop."
  20. Impressive setup. I'm afraid I like math approach. Yes the KT66 was the lower power tube while the KT 88 was a higher power device. KT stands for kinkless tetrode .
  21. They both came from the same seller.
  22. My latest coin one of the harder dates of the Edward series. All I need is a high grade 1905 florin at a good price. I live in hope. I notice that Britannia's face seems worn but in the hand it's pretty good.
  23. My latest penny. Not a rare date but but a nice example.
  24. Yes I met Small when I was working at Sydney Uni. Small signal analysis is where you linearize a nonlinear transfer function around an operating point and is much used in electronic circuit design. I can also remember Goodmans suggesting that you mounted speakers in a concrete column. I have never seen any analysis of this but I suspect it would involve circular harmonics leading to Bessel's partial differential equations . Any relation of small signal to Richard Small is incidental as small signal analysis was used mainly in electronic circuit design to accommodate the non linear nature of vacuum tubes, FETs and BJTs. I'm afraid my audio is entirely shop brought with a Denon AVR X250BT 5.1 tuner amp and Wharfedale Alantic SE Series speakers 2 AT-400 SE and 2 AT200 SE. The Denon employs a white noise source to balance the speakers but does not support a microphone like the earlier Denon I had so I use a sound level app on my phone that seems to deliver reasonable results. I changed the earlier Denon as it did not support 4k HDMI. Earlier on in my career I worked at the MO Valve company where they made the KT 88 and KT 66 tubes. not realizing that they would be sought after today by some audio buffs who want to chase the Vacuum tube sound.
  25. Hot Cross buns one a penny two a penny.
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