[djtosko]

Buy ICOM A4. Best solution for you.

when you found icom a5 you can buy ...end sell me ok ?

[B1257]

you mentioned a exclusively made heatsink , could you show us a little more information of it ?... Regards, RReader

First of all, sorry for the delay, work nothing more...
Now here are some pictures about the heatsink I made.


Picture1 As you can see in my way the heatsink is made with two parts. The main center plate which will later touch the complete case for a better heat dissipation. And second the small CPU plate which is glued with a special Thermal Bound paste for FPGA chips on the center plate. You can see the compound type on the picture.


Picture2 Shows the Temp in C° after an idle running time of the head about 30 minutes, without any cooling.


Picture3 Original there are two pads for the cooling, but not one is touching the case, after a longer time the complete case will warm up in a way that the both chips are near out of max temp range, which is in a normal grade about 70°C. For our heatsink I will use a small pad for the MICREL chip to give me the right contact to my center plate. Second reason is that the pad gives me a little bit place for a realignment to center the main plate with both chips.


Picture4 You can see new srewls and bolts to compensate the new height. The screwls dimension of the innerside srewls is 2.5x12mm (countersunk bolt, this is important, because we cant fix the center place in the case if there is not enough place with normal screwls.)


Picture5 Be carefull to center the plate exactly with vary the three plastic bolts, may you have to cut it a litlle bit. Check the space between the case and the center plate one or more times. Take care that both chips are touching the heatsink, because some cases can vary the height.


Picture6 Apply compound paste to the center plate, where the heatsink is later touching the case for the best heat dissipation.


Picture7 For the best way take care that the complete heatsink is touching the case. See the red arrow.

After the heatsink mod the temps are always inside the specs. I remember 5 hours idle running about 40.5C° room temp about 26°C.

I hope this helps you to mount the heatsink in a proper way.

Anyway if the instruction helps press Reputation and Thank you button.

Regards,
B1257

[osd]

@ B1257 - if you used thermalpads there, and it look like you used, you shouldnt use any thermal grease on it !, because it is killing thermal pad, take a look in laptops where BGA GPU or north bridges sometimes used 40-60 Watts and are on thermalpads ( which is bad design, should be copper+thermal grease) but there is never ever thermalpad + grease or glue ...NEVER.

Another thing, what thermalpads you were use ? if its not good quality you will boil chips. On the outside of casing it wont be hot, but chips inside.... The best i have ever used are Laird 5W (700 series) its expensive but almost like copper. You should use them without any glue or grease, it wont move.
Measuring temperature in outside dont tell you anything, chip can have 100C and with bad thermalpad you will have outside 40, because cheap thermalpad dont conduct so well. You should put temperature sensor between chip and thermalpad and check this value.


Important thing is that in China there are many iComs manufacturers, some are very shitty some are good, all looks the same outside. I was buy two. First was working 2 weeks, go to China for repair, after another 2 weeks the same... Secound one is working great until these days, and this seller explain me situation about China iComs. All you need is good and honest seller - yes you can find that sellers in China .

[B1257]

@ B1257 - if you used thermalpads there, and it look like you used, you shouldnt use any thermal grease on it !, because it is killing thermal pad, take a look in laptops where BGA GPU or north bridges sometimes used 40-60 Watts and are on thermalpads ( which is bad design, should be copper+thermal grease) but there is never ever thermalpad + grease or glue ...NEVER.

Sorry but you´re wrong may you cant see it, but in Picture 3 the left one is a thermal pad, the right one is the Alu piece which is later glued to the center plate. I never wrote thate I made compound on the pad and the pad is of course another one like the China people will use. About the quality, it is my personal fix of my head. The heads are working fine I know the distributer more than 8 years.

I am developing hardware more than 20 years--))

Best Regards,
B1257

[bawareca]

Good write-up, thanks. I still use ICOM A1 and it works fine and forever. I can program a cra for hour or more in a 35C heat and there will never be a problem. I now just put a WIFI dongle in the USB port and use it wireless with ISTA D.