Then if you go down on that page I linked it will describe the capacitors on the high voltage circuit on the display board
Knowledge Base Article 5BMC2857A6
Issue
On my R71, the frequency display blanks out periodically with only decimal points remaining.
Resolution
Display DC-DC converter has noisy output.
Replace all of the following dried-out electrolytic capacitors on the display unit: C15, C16, C17, C18, C19, C20, C21 and C22. These capacitors are bright yellow when new. If they have turned brown, they are old and dried out.
While servicing the DC-DC converter section examine the board closely for cracked solder joints as this section of the radio runs hot. Also, we recommend reprogramming the RAM card after servicing the DC-DC section.
Right now there are listings on Ebay from Canada with capacitor replacement kits
Icom IC-R71A-R71E HF Receiver Capacitor Replacement Kit
David Kb7uns