I was looking in some old 60s Radcoms for designs/ideas for a transmitter for 7MHz using Germanium transistors for a club project.
Of course I cannot find the actual article now but it was from 1964-1967 vintage and described some RF power devices that were now available for HF but these were Silicon. They cost ?46 each in 1966 pounds. From the same period a fully qualified Junior Lab Tech for the BBC earned ?21 14s 10d a week before tax.
And as my namesake says this was when that nice Mr. Wilson was PM and his Chancellor George (hic) Brown raised the high level of income tax to 95%. With a super tax level for the very rich of 110% (i.e. you had to pay more tax than you earned).
So ?46 was probably approaching a months take home pay for such a Junior Lab Tech.
The BLY17 was available from Mullard for ?15 each. 5 of them would make a 100W pep PA for HF with 2W of drive. ?75 for the devices and you needed a 36V PSU. That is getting on for 2months take home pay.
OC170 transistors were usable to beyond 144MHz and were available then for 6/- each.
?100 in 1966 is the equivalent of ?1733 in 2022 for reference.
73
Andy
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On 01/08/2022 17:30, Andy G0FTD via groups.io wrote:
On Mon, Aug 1, 2022 at 04:23 PM, Andy G0FTD wrote:
On Mon, Aug 1, 2022 at 03:52 PM, John Rabson wrote:
I seem to recall a question in my IEE (1966?) fiinals which
asked me to outline the design of a 1kW transistor AF amplifier.
I asked a neighbour who worked in semiconductor research if the
examiners were serious. He declined to discuss the matter.
1966 ?
How many white spot transistors did he expect you to use ?
Not sure if that term was used outside the UK.
1966 was still when a single tranny with a whopping Ft=1Mhz would
purchase you two homes.
Enter the white and red spot samples, out of spec parts sold for a
weeks wages instead ;-)
Can't remember what the difference was between the colours though,
AF vs RF maybe ?
Oh well, I thought it best to go on a fact finding mission for this.
I checked my archives of Practical Wireless from 1966 and found nothing, but I did in 1962
find references to Red / White and Yellow spot transistors.
White = 4 Shillings and 6 pence
Red = 3 Shillings and 6 pence
Yellow = 2 Shilling and 9 pence
so I guess the Whitespot was more RF (RF probably being quite low in those days, 1-10Mhz ?).
Average UK wages in 1962 were 317 Shillings per month.
Reference
Assuming a 40 hour week meant that you worked? 2 hours for one transistor.
Now consider a modern transistor or FET such as a BS170 / 2N2222 / BC108 sold typically for ?0.25 (25 pence).
Similar output at RF, but usable from at least 30-200Mhz.
Using the baseline of current UK minimum legal wage at ?9.50 / hour equate to buying 76 higher spec devices
compared to the same wage rate, or 2 hours compared to less than 2 minutes per device.
But actually you worked a little bit more time that these examples because income tax is not included.
Typically that might have been about 1/3rd more, unless you were paying super tax which was 95%
of your income.
Whence the Beatles sang "there's one for you, nineteen for me" (slagging off Harold Wilson).
I've attached the pic I took a few years ago of Mr Wilson's grave.
- Andy (delivering the goods as usual) -
