In my experience, action cam underwater / weatherproof transparent cases have buttons that are quite difficult to use. This seems mostly because they are assembled with no lubricant.
Above, the button in the genuine Sjcam SJ8 has a stainless spring, shaped washer, two 6x2x2mm orings, and a 2.5mm E clip. This pic shows that the thing is assembled dry which makes operating pressure high, and in any event not smooth as the button shaft is not particularly smooth. Continue reading Refurbishing the push button in action cam cases
A continuing frustration is garden hose maintenance.
We use reinforced hose that comprises essentially three layers, an inner plastic layer, a braided fibre reinforcing layer and another layer of plastic. Though these layers are bonded in new hose, there is potential for them to separate in service resulting in the reinforcing braid pulling back into the hose length and allowing the hose to expand in diameter at that point (lacking the benefit of the reinforcement). At this point failure of the hose by bursting is inevitable, sooner rather than later.
Some hoses are supplied fitted with factory crimped ferrules, and experience is that they have lasted well except that the fittings are plastic and break if subjected to rough treatment.
User serviceable screw collets fail, either through failure of the collets, or just the outcome of the screw collar loosening and resultant pull-back of the reinforcing braid.
What is needed is a tough and durable coupler with an easily applied ‘permanent’ clamp.
I have conducted a trial of brass fittings modified to remove the screw collar and nylon collet, then used with a stainless steel stepless one ear clamp.
Above at left is the unmodified coupler, and at right the coupler with the collet and screw collar discarded, thread turned off the coupler, and a one ear clamp for installation. Continue reading Garden hose couplers – there has to be a better way
I bought an inexpensive Chinese quartz wristwatch for my grandson, about $11 inc post).
Importantly it claims to be water resistant to 3atm (3bar), and the pics given on eBay clearly showed a screw on back (even weeks after becoming aware that is deceptive and misleading). Continue reading Cheap Chinese wristwatch #2
I bought an inexpensive Chinese manual wind wristwatch for my grandson. It is a skeleton style watch based on the communist Tongji movement.
Above, the watch looking pretty flashy in gold coloured finish. The gold plate wore off the band in just a few days to reveal a brass band tarnishing by the hour. The bezel is probably base metal and will corrode in no time. Continue reading Cheap Chinese wristwatch #1
Lets use a simple test circuit to review the meaning of some oft misused terms associated with VNA and antenna analyser measurements.
Above, the test circuit is a nominally 220pF COG capacitor connected between tx and rx ports of a two port VNA. An extra 1Ω series resistance is included to model the likely effect of capacitor ESR. Continue reading Ham grade analysers and VNAs often use unconventional meanings for well known terms
I couldn’t help myself, Mandarins are falling and I had to try a marmalade of Mandarins and Limes. I made a small batch of marmalade using 50% Tahitian Lime and 50% Imperial Mandarin. Raw sugar was one third the added sugar to impart a darker colour.
The marmalade is light coloured, sweet and tangy. Continue reading Mandarin & Lime Marmalade
Last of the trial recipes was a small batch of marmalade using 50% Australian Lime and 50% Eureka Lemon.
The marmalade is light coloured, sweet and tangy, but a hint of the bitter lemon aspect of the Eureka. Continue reading Australian Lime & Lemon Marmalade
We had a small excess of Tahitian Limes ripen, so I tried a test batch of Tahitian Lime Marmalade.
The marmalade is light coloured, sweet and tangy.
The downside is that the fruit is full of seeds, not just in the equatorial plane but distributed right through it, so scooping seeds out is quite a task.
It is the first time I have made jam from these, and essentially I used the 40:60 mix from FAO’s Generic Jam Recipe, though being limes no acid was needed, in fact about 6g of Sodium Bicarbonate per kg of fruit to achieve the ideal pH of 3.2-3.3. The limes were cooked to release some Pectin, but a little Pectin 10g/kg) was added as the cooked fruit gave a slightly weak reaction in Methylated Spirits.
Endpoint was assessed by measuring Brix using a refractometer, confirmed by setting a drop of jam on a cold plate.
Winter has arrived, but so has the citrus fruit matured.
I picked a bucket of Australian Limes which had ripened to the point of mostly yellow skin.
Being a bit partial to Lime Marmalade, I have cooked up a couple of 4kg batches of high fruit content marmalade and bottled it.
It is the first time I have made jam from these, and essentially I used the 45:55 mix from FAO’s Generic Jam Recipe, though being limes no acid was needed, in fact about 2.5g of Sodium Bicarbonate per kg of fruit to achieve the ideal pH of 3.2-3.3. The limes were cooked to release some Pectin, but a little Pectin 6g/kg) was added as the cooked fruit gave a slightly weak reaction in Methylated Spirits.
Endpoint was assessed by weighing the pot from time to time until the jam had cooked down to the target 4kg of product.
We bought a cheap wheelbarrow 6 years ago, and it is like grandfather’s axe: 6 new handles and 3 new heads and its 100 years old.
This thing has had numerous tyre patches (some due to defects in the cheap Chines tubes), three new tubes, two new tyres, it is trying to rust out, and the concreters working here last Winter used it to carry fully loads of concrete… splitting the side of the poly tray. The split has been growing slowly with temperature cycling, I should have drilled some small holes to defuse the stress raiser at the ends of the split.
Whilst I have replaced the barrow, we continue to use this one to exhaustion… and I succumbed and plastic welded the split in the tub. A similar bead on the inside dressed with a burr to remove edged that would catch on tools compete the job… we will se how long it lasts.